rt_device_write/read return data type as rt_ssize_t

rt_ssize_t can give negative error code, which follows the unix style correctly

bsp/CME_M7/drivers/emac.c

@@ -228,13 +228,13 @@ static rt_err_t rt_cme_eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_cme_eth_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_cme_eth_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_cme_eth_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_cme_eth_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/Infineon/libraries/HAL_Drivers/drv_i2c.c

@@ -90,7 +90,7 @@ static int ifx_i2c_write(struct ifx_i2c *hi2c, uint16_t slave_address, uint8_t *
     return 0;
 }
 
-static rt_size_t _i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t _i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/Infineon/psoc6-pioneerkit_modus/drivers/uart.c

@@ -94,7 +94,7 @@ static rt_err_t rt_uart_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_uart_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_uart_read (rt_device_t dev, rt_off_t pos, void* buffer,
                                  rt_size_t size)
 {
     rt_uint8_t* ptr;
@@ -154,7 +154,7 @@ static rt_size_t rt_uart_read (rt_device_t dev, rt_off_t pos, void* buffer,
     return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
 }
 
-static rt_size_t rt_uart_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_uart_write (rt_device_t dev, rt_off_t pos,
                                 const void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;

bsp/acm32/acm32f0x0-nucleo/drivers/drv_i2c.c

@@ -84,7 +84,7 @@ static int acm32_i2c_write(struct acm32_i2c *hi2c, uint16_t slave_address, uint8
     return 0;
 }
 
-static rt_size_t _i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t _i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/acm32/acm32f0x0-nucleo/drivers/drv_uart.c

@@ -275,7 +275,7 @@ static void dma_rx_done_isr(struct rt_serial_device *serial)
     HAL_UART_Receive_DMA(&(uart->handle), &rx_fifo->buffer[rx_fifo->put_index], serial->config.bufsz);
 }
 
-static rt_size_t _uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t _uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     struct acm32_uart *uart;
     RT_ASSERT(serial != RT_NULL);

bsp/acm32/acm32f4xx-nucleo/drivers/drv_uart.c

@@ -274,7 +274,7 @@ static void dma_rx_done_isr(struct rt_serial_device *serial)
     HAL_UART_Receive_DMA(&(uart->handle), &rx_fifo->buffer[rx_fifo->put_index], serial->config.bufsz);
 }
 
-static rt_size_t _uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t _uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     struct acm32_uart *uart;
     RT_ASSERT(serial != RT_NULL);

bsp/airm2m/air105/libraries/rt_drivers/drv_i2c.c

@@ -14,10 +14,10 @@
 #ifdef BSP_USING_I2C
 
 static struct rt_i2c_bus_device prv_air105_i2c;
-static rt_size_t air105_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t air105_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
                                  struct rt_i2c_msg msgs[],
                                  rt_uint32_t num);
-static rt_size_t air105_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t air105_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
                                  struct rt_i2c_msg msgs[],
                                  rt_uint32_t num);
 static rt_err_t air105_i2c_bus_control(struct rt_i2c_bus_device *bus,
@@ -32,7 +32,7 @@ static const struct rt_i2c_bus_device_ops air105_i2c_ops =
 };
 
 
-static rt_size_t air105_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t air105_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
                                  struct rt_i2c_msg msgs[],
                                  rt_uint32_t num)
 {
@@ -81,7 +81,7 @@ static rt_size_t air105_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
     }
     return i;
 }
-static rt_size_t air105_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t air105_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
                                  struct rt_i2c_msg msgs[],
                                  rt_uint32_t num)
 {

bsp/airm2m/air105/libraries/rt_drivers/drv_usart_v2.c

@@ -262,7 +262,7 @@ static int air105_getc(struct rt_serial_device *serial)
     }
 }
 
-static rt_size_t air105_transmit(struct rt_serial_device     *serial,
+static rt_ssize_t air105_transmit(struct rt_serial_device     *serial,
                                        rt_uint8_t           *buf,
                                        rt_size_t             size,
                                        rt_uint32_t           tx_flag)

bsp/airm2m/air32f103/libraries/rt_drivers/drv_usart.c

@@ -275,7 +275,7 @@ static int air32_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t air32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t air32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     return 0;
 }

bsp/allwinner/d1s/ports/partition/partition.c

@@ -78,7 +78,7 @@ static rt_err_t partition_control(rt_device_t dev, rt_uint8_t cmd, void *args)
     return RT_EOK;
 }
 
-static rt_size_t partition_read(rt_device_t dev,
+static rt_ssize_t partition_read(rt_device_t dev,
                                    rt_off_t pos,
                                    void* buffer,
                                    rt_size_t size)
@@ -93,7 +93,7 @@ static rt_size_t partition_read(rt_device_t dev,
     return rt_device_read(part->block_device, pos + part->partition->offset/part->sector_size, buffer, size);
 }
 
-static rt_size_t partition_write(rt_device_t dev,
+static rt_ssize_t partition_write(rt_device_t dev,
                                     rt_off_t pos,
                                     const void* buffer,
                                     rt_size_t size)

bsp/allwinner/libraries/drivers/drv_i2c.c

@@ -24,7 +24,7 @@ struct hal_i2c_bus
 };
 
 //connect am drv to rt drv.
-static rt_size_t _i2c_master_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg *msgs, rt_uint32_t num)
+static rt_ssize_t _i2c_master_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg *msgs, rt_uint32_t num)
 {
     struct hal_i2c_bus *_i2c_bus = (struct hal_i2c_bus *)bus;
     struct rt_i2c_msg *msg;

bsp/allwinner/libraries/drivers/drv_uart.c

@@ -388,7 +388,7 @@ static rt_err_t _uart_configure(struct rt_serial_device *serial, struct serial_c
 static rt_err_t _uart_control(struct rt_serial_device *serial, int cmd, void *arg);
 static int _uart_putc(struct rt_serial_device *serial, char c);
 static int _uart_getc(struct rt_serial_device *serial);
-static rt_size_t _uart_transmit(struct rt_serial_device *serial,
+static rt_ssize_t _uart_transmit(struct rt_serial_device *serial,
                                 rt_uint8_t *buf, rt_size_t size, rt_uint32_t tx_flag);
 
 const struct rt_uart_ops _uart_ops =
@@ -720,7 +720,7 @@ static int _uart_getc(struct rt_serial_device *serial)
     return data;
 }
 
-static rt_size_t _uart_transmit(struct rt_serial_device *serial,
+static rt_ssize_t _uart_transmit(struct rt_serial_device *serial,
                                 rt_uint8_t *buf, rt_size_t size, rt_uint32_t tx_flag)
 {
     struct sunxi_uart *uart;

bsp/allwinner/libraries/drivers/sdmmc/drv_sdmmc.c

@@ -232,7 +232,7 @@ rt_err_t sdmmc_deinit(rt_device_t dev)
     return 0;
 }
 
-static rt_size_t sdmmc_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t sdmmc_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     ssize_t ret, rsz, trsz, msz = 0;
     struct rt_device_blk_geometry *geometry;
@@ -309,7 +309,7 @@ static rt_err_t sdmmc_close(rt_device_t dev)
     return 0;
 }
 
-static rt_size_t sdmmc_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t sdmmc_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     int err = -1;
     ssize_t ret, wsz, twsz, msz = 0;

bsp/allwinner/libraries/drivers/touch/drv_touch.c

@@ -152,7 +152,7 @@ int rt_touch_write(rt_uint16_t addr, void *data_buf, size_t data_len)
         return -1;
 }
 
-static rt_size_t touch_readpoint(struct rt_touch_device *touch, void *buf, rt_size_t touch_num)
+static rt_ssize_t touch_readpoint(struct rt_touch_device *touch, void *buf, rt_size_t touch_num)
 {
     rt_device_t device;
     struct rt_touch_data *data = (struct rt_touch_data *)buf;

bsp/allwinner/libraries/sunxi-hal/hal/source/gmac/hal_geth.c

@@ -743,14 +743,14 @@ static rt_err_t rt_geth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_geth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_geth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     printf("gmac read\n");
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_geth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_geth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     printf("gmac write\n");
     rt_set_errno(-RT_ENOSYS);

bsp/allwinner_tina/drivers/drv_uart.c

@@ -40,7 +40,7 @@ static rt_err_t uart_configure(struct rt_serial_device *serial, struct serial_co
 static rt_err_t uart_control(struct rt_serial_device *serial, int cmd, void *arg);
 static int      uart_putc(struct rt_serial_device *serial, char c);
 static int      uart_getc(struct rt_serial_device *serial);
-static rt_size_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
+static rt_ssize_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
 
 void     uart_irq_handler(int irqno, void *param);
 
@@ -284,7 +284,7 @@ static int uart_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     return (0);
 }

bsp/amebaz/drivers/drv_uart.c

@@ -31,7 +31,7 @@ static rt_err_t  ameba_uart_configure    (struct rt_serial_device *serial, struc
 static rt_err_t  ameba_uart_control      (struct rt_serial_device *serial, int cmd, void *arg);
 static int       ameba_uart_putc         (struct rt_serial_device *serial, char c);
 static int       ameba_uart_getc         (struct rt_serial_device *serial);
-static rt_size_t ameba_uart_dma_transmit (struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
+static rt_ssize_t ameba_uart_dma_transmit (struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
 
 static void ameba_uart_irq(uint32_t id, SerialIrq event);
 
@@ -118,7 +118,7 @@ static int ameba_uart_getc (struct rt_serial_device *serial)
     return serial_getc(&uart->serial);
 }
 
-static rt_size_t ameba_uart_dma_transmit (struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t ameba_uart_dma_transmit (struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     return (0);
 }

bsp/apm32/libraries/Drivers/drv_eth.c

@@ -412,13 +412,13 @@ static rt_err_t rt_apm32_eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_apm32_eth_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_apm32_eth_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_apm32_eth_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_apm32_eth_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/apollo2/board/flash.c

@@ -75,7 +75,7 @@ static rt_err_t rt_flash_control(rt_device_t dev, int cmd, void *args)
     return RT_EOK;
 }
 
-static rt_size_t rt_flash_read(rt_device_t dev,
+static rt_ssize_t rt_flash_read(rt_device_t dev,
                                    rt_off_t pos,
                                    void* buffer,
                                    rt_size_t size)
@@ -85,7 +85,7 @@ static rt_size_t rt_flash_read(rt_device_t dev,
     return size;
 }
 
-static rt_size_t rt_flash_write(rt_device_t dev,
+static rt_ssize_t rt_flash_write(rt_device_t dev,
                                     rt_off_t pos,
                                     const void* buffer,
                                     rt_size_t size)

bsp/apollo2/board/rtc.c

@@ -29,7 +29,7 @@ static rt_err_t rt_rtc_open(rt_device_t dev, rt_uint16_t oflag)
     return RT_EOK;
 }
 
-static rt_size_t rt_rtc_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_rtc_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     return 0;
 }

bsp/at32/libraries/rt_drivers/drv_emac.c

@@ -413,14 +413,14 @@ static rt_err_t rt_at32_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_at32_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_at32_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     LOG_D("emac read");
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_at32_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_at32_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     LOG_D("emac write");
     rt_set_errno(-RT_ENOSYS);

bsp/at32/libraries/rt_drivers/drv_usart.c

@@ -333,7 +333,7 @@ static void at32_dma_config(struct rt_serial_device *serial, rt_ubase_t flag)
     nvic_irq_enable(instance->irqn, 1, 0);
 }
 
-static rt_size_t at32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t at32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     struct at32_uart *instance;
     instance = (struct at32_uart *) serial->parent.user_data;

bsp/at91/at91sam9260/drivers/macb.c

@@ -514,13 +514,13 @@ static rt_err_t rt_macb_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_macb_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_macb_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_macb_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_macb_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/at91/at91sam9g45/drivers/macb.c

@@ -514,13 +514,13 @@ static rt_err_t rt_macb_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_macb_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_macb_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_macb_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_macb_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/bluetrum/libraries/hal_drivers/drv_usart.c

@@ -209,7 +209,7 @@ static int ab32_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t ab32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t ab32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     return -1;
 }

bsp/dm365/drivers/davinci_emac.c

@@ -1585,16 +1585,14 @@ static rt_err_t rt_davinci_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_davinci_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_davinci_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
-static rt_size_t rt_davinci_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_davinci_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
 static rt_err_t rt_davinci_emac_control(rt_device_t dev, int cmd, void *args)

bsp/efm32/drv_ethernet.c

@@ -606,7 +606,7 @@ static rt_err_t efm_eth_close(rt_device_t dev)
  * @return
  *   Number of read bytes
  ******************************************************************************/
-static rt_size_t efm_eth_read(
+static rt_ssize_t efm_eth_read(
     rt_device_t     dev,
     rt_off_t        pos,
     void            *buffer,
@@ -639,7 +639,7 @@ static rt_size_t efm_eth_read(
  * @return
  *   Number of written bytes
  ******************************************************************************/
-static rt_size_t efm_eth_write (
+static rt_ssize_t efm_eth_write (
     rt_device_t     dev,
     rt_off_t        pos,
     const void      *buffer,

bsp/efm32/drv_iic.c

@@ -182,7 +182,7 @@ static rt_err_t rt_iic_close(rt_device_t dev)
  * @return
  *   Error code
  ******************************************************************************/
-static rt_size_t rt_iic_read (
+static rt_ssize_t rt_iic_read (
     rt_device_t     dev,
     rt_off_t        pos,
     void*           buffer,
@@ -343,7 +343,7 @@ static rt_size_t rt_iic_read (
  * @return
  *   Error code
  ******************************************************************************/
-static rt_size_t rt_iic_write (
+static rt_ssize_t rt_iic_write (
     rt_device_t     dev,
     rt_off_t        pos,
     const void*     buffer,

bsp/efm32/drv_leuart.c

@@ -247,7 +247,7 @@ static rt_err_t rt_leuart_close(rt_device_t dev)
  * @return
  *   Number of read bytes
  ******************************************************************************/
-static rt_size_t rt_leuart_read (
+static rt_ssize_t rt_leuart_read (
     rt_device_t     dev,
     rt_off_t        pos,
     void            *buffer,
@@ -372,7 +372,7 @@ static rt_size_t rt_leuart_read (
  * @return
  *   Number of written bytes
  ******************************************************************************/
-static rt_size_t rt_leuart_write (
+static rt_ssize_t rt_leuart_write (
     rt_device_t     dev,
     rt_off_t        pos,
     const void*     buffer,

bsp/efm32/drv_rtc.c

@@ -49,7 +49,7 @@ static rt_err_t rt_rtc_open(rt_device_t dev, rt_uint16_t oflag)
     return RT_EOK;
 }
 
-static rt_size_t rt_rtc_read(
+static rt_ssize_t rt_rtc_read(
     rt_device_t     dev,
     rt_off_t        pos,
     void*           buffer,

bsp/efm32/drv_sdcard.c

@@ -136,7 +136,7 @@ static void efm_spiSd_speed(rt_uint8_t level)
  * @return
  *   Number of read bytes
  ******************************************************************************/
-static rt_size_t efm_spiSd_read(void *buffer, rt_size_t size)
+static rt_ssize_t efm_spiSd_read(void *buffer, rt_size_t size)
 {
     RT_ASSERT(spi != RT_NULL);
 
@@ -807,7 +807,7 @@ static rt_err_t rt_spiSd_close(rt_device_t dev)
  * @return
  *   Number of read sectors
  ******************************************************************************/
-static rt_size_t rt_spiSd_read(
+static rt_ssize_t rt_spiSd_read(
     rt_device_t     dev,
     rt_off_t        sector,
     void            *buffer,
@@ -897,7 +897,7 @@ static rt_size_t rt_spiSd_read(
  * @return
  *   Number of written sectors
  ******************************************************************************/
-static rt_size_t rt_spiSd_write (
+static rt_ssize_t rt_spiSd_write (
     rt_device_t     dev,
     rt_off_t        sector,
     const void      *buffer,

bsp/efm32/drv_usart.c

@@ -354,7 +354,7 @@ static rt_err_t rt_usart_close(rt_device_t dev)
  * @return
  *  Number of read bytes
  ******************************************************************************/
-static rt_size_t rt_usart_read (
+static rt_ssize_t rt_usart_read (
     rt_device_t     dev,
     rt_off_t        pos,
     void            *buffer,
@@ -550,7 +550,7 @@ static rt_size_t rt_usart_read (
  * @return
  *   Number of written bytes
  ******************************************************************************/
-static rt_size_t rt_usart_write (
+static rt_ssize_t rt_usart_write (
     rt_device_t     dev,
     rt_off_t        pos,
     const void*     buffer,

bsp/essemi/es32f0654/drivers/drv_i2c.c

@@ -106,7 +106,7 @@ static void _i2c_init(void)
 #endif
 }
 
-static rt_size_t es32f0_master_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t es32f0_master_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num)
 {

bsp/essemi/es32f369x/drivers/drv_i2c.c

@@ -265,7 +265,7 @@ SUCCESS:
     return OK;
 }
 
-static rt_size_t es32f3_master_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t es32f3_master_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num)
 {

bsp/essemi/es32f369x/drivers/drv_uart.c

@@ -721,7 +721,7 @@ static int es32f3x_getc(struct rt_serial_device *serial)
 /**
  * DMA transmit
  */
-static rt_size_t es32f3x_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t es32f3x_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     struct es32_uart *uart;
 

bsp/frdm-k64f/board/drv_emac.c

@@ -229,16 +229,14 @@ static rt_err_t k64_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t k64_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t k64_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
-static rt_size_t k64_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t k64_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
 static rt_err_t k64_emac_control(rt_device_t dev, int cmd, void *args)

bsp/ft2004/drivers/drv_eth.c

@@ -250,14 +250,14 @@ static rt_err_t rt_ft2004_gmac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_ft2004_gmac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_ft2004_gmac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     LOG_D("gmac read");
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_ft2004_gmac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_ft2004_gmac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     LOG_D("gmac write");
     rt_set_errno(-RT_ENOSYS);

bsp/ft32/libraries/Drivers/drv_usart.c

@@ -305,7 +305,7 @@ static int ft32_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t ft32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t ft32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     RT_ASSERT(serial != RT_NULL);
     RT_ASSERT(buf != RT_NULL);

bsp/fujitsu/mb9x/mb9bf506r/drivers/nand.c

@@ -358,7 +358,7 @@ static rt_err_t rt_nand_close(rt_device_t dev)
 }
 
 /* nand device read */
-static rt_size_t rt_nand_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_nand_read (rt_device_t dev, rt_off_t pos, void* buffer,
                                rt_size_t size)
 {
     rt_ubase_t block;           /* block of position */
@@ -456,7 +456,7 @@ static int rt_nand_eraseblock_writepage(struct rt_device_nand* nand,
 }
 
 /* nand device write */
-static rt_size_t rt_nand_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_nand_write (rt_device_t dev, rt_off_t pos,
                                 const void* buffer, rt_size_t size)
 {
     rt_ubase_t block, page;

bsp/fujitsu/mb9x/mb9bf568r/drivers/led.c

@@ -72,7 +72,7 @@ static rt_err_t rt_led_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
                               rt_size_t size)
 {
     rt_ubase_t index = 0;
@@ -97,7 +97,7 @@ static rt_size_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
     return index;
 }
 
-static rt_size_t rt_led_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_led_write (rt_device_t dev, rt_off_t pos,
                                const void* buffer, rt_size_t size)
 {
     rt_ubase_t index = 0;

bsp/fujitsu/mb9x/mb9bf568r/drivers/serial.c

@@ -105,7 +105,7 @@ static rt_err_t rt_serial_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
                                  rt_size_t size)
 {
     rt_uint8_t* ptr;
@@ -164,7 +164,7 @@ static rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
     return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
 }
 
-static rt_size_t rt_serial_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_serial_write (rt_device_t dev, rt_off_t pos,
                                   const void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;

bsp/fujitsu/mb9x/mb9bf618s/drivers/led.c

@@ -75,7 +75,7 @@ static rt_err_t rt_led_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
                               rt_size_t size)
 {
     rt_ubase_t index = 0;
@@ -100,7 +100,7 @@ static rt_size_t rt_led_read (rt_device_t dev, rt_off_t pos, void* buffer,
     return index;
 }
 
-static rt_size_t rt_led_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_led_write (rt_device_t dev, rt_off_t pos,
                                const void* buffer, rt_size_t size)
 {
     rt_ubase_t index = 0;

bsp/fujitsu/mb9x/mb9bf618s/drivers/serial.c

@@ -105,7 +105,7 @@ static rt_err_t rt_serial_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
+static rt_ssize_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
                                  rt_size_t size)
 {
     rt_uint8_t* ptr;
@@ -164,7 +164,7 @@ static rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer,
     return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
 }
 
-static rt_size_t rt_serial_write (rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_serial_write (rt_device_t dev, rt_off_t pos,
                                   const void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;

bsp/gd32/arm/libraries/gd32_drivers/drv_sdio.c

@@ -232,7 +232,7 @@ static rt_err_t rt_sdcard_close(rt_device_t dev)
 }
 
 static uint32_t dma_buffer[SECTOR_SIZE/sizeof(uint32_t)];
-static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     RT_ASSERT(dev != RT_NULL);
 
@@ -283,7 +283,7 @@ static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
     }
 }
 
-static rt_size_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 #define WR_RETRY_TIMES 2
 

bsp/gd32105c-eval/drivers/drv_i2c.c

@@ -225,7 +225,7 @@ static int gd32_i2c_write(rt_uint32_t i2c_periph, uint16_t slave_address, uint8_
     return 0;
 }
 
-static rt_size_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/gd32107c-eval/drivers/drv_i2c.c

@@ -225,7 +225,7 @@ static int gd32_i2c_write(rt_uint32_t i2c_periph, uint16_t slave_address, uint8_
     return 0;
 }
 
-static rt_size_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/gd32303e-eval/drivers/drv_i2c.c

@@ -226,7 +226,7 @@ static int gd32_i2c_write(rt_uint32_t i2c_periph, uint16_t slave_address, uint8_
     return 0;
 }
 
-static rt_size_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/gd32450z-eval/drivers/drv_enet.c

@@ -200,16 +200,14 @@ static rt_err_t gd32_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t gd32_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t gd32_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
-static rt_size_t gd32_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t gd32_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
 static rt_err_t gd32_emac_control(rt_device_t dev, int cmd, void *args)

bsp/gd32e230k-start/drivers/drv_i2c.c

@@ -227,7 +227,7 @@ static int gd32_i2c_write(rt_uint32_t i2c_periph, uint16_t slave_address, uint8_
     return 0;
 }
 
-static rt_size_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t gd32_i2c_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;
     rt_uint32_t i;

bsp/hc32/libraries/hc32_drivers/drv_eth.c

@@ -178,14 +178,14 @@ static rt_err_t rt_hc32_eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_hc32_eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_hc32_eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     LOG_D("eth read");
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_hc32_eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_hc32_eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     LOG_D("eth write");
     rt_set_errno(-RT_ENOSYS);

bsp/hc32/libraries/hc32_drivers/drv_usart.c

@@ -374,7 +374,7 @@ static int hc32_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t hc32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t hc32_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
 #ifdef RT_SERIAL_USING_DMA
     struct hc32_uart *uart;

bsp/hc32l136/drivers/drv_usart.c

@@ -383,7 +383,7 @@ static int hc32_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t hc32_dma_transmit(struct rt_serial_device *serial,
+static rt_ssize_t hc32_dma_transmit(struct rt_serial_device *serial,
                                    rt_uint8_t *buf,
                                    rt_size_t size,
                                    int direction)

bsp/hpmicro/hpm6750evk/board/eth_phy_port.c

@@ -101,14 +101,14 @@ static rt_phy_status phy_init(void *object, rt_uint32_t phy_addr, rt_uint32_t sr
     return PHY_STATUS_OK;
 }
 
-static rt_size_t phy_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t phy_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     *(uint16_t *)data = enet_read_phy(((struct rt_mdio_bus *)bus)->hw_obj, addr, reg);
 
     return size;
 }
 
-static rt_size_t phy_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t phy_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     enet_write_phy(((struct rt_mdio_bus *)bus)->hw_obj, addr, reg,  *(uint16_t *)data);
 

bsp/hpmicro/hpm6750evkmini/board/eth_phy_port.c

@@ -101,14 +101,14 @@ static rt_phy_status phy_init(void *object, rt_uint32_t phy_addr, rt_uint32_t sr
     return PHY_STATUS_OK;
 }
 
-static rt_size_t phy_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t phy_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     *(uint16_t *)data = enet_read_phy(((struct rt_mdio_bus *)bus)->hw_obj, addr, reg);
 
     return size;
 }
 
-static rt_size_t phy_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t phy_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     enet_write_phy(((struct rt_mdio_bus *)bus)->hw_obj, addr, reg,  *(uint16_t *)data);
 

bsp/hpmicro/libraries/drivers/drv_dao.c

@@ -214,7 +214,7 @@ static rt_err_t hpm_dao_stop(struct rt_audio_device* audio, int stream)
     return RT_EOK;
 }
 
-static rt_size_t hpm_dao_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
+static rt_ssize_t hpm_dao_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
 {
     RT_ASSERT(audio != RT_NULL);
 

bsp/hpmicro/libraries/drivers/drv_enet.c

@@ -196,12 +196,12 @@ static rt_err_t rt_hpm_eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_hpm_eth_read(rt_device_t dev, rt_off_t pos, void * buffer, rt_size_t size)
+static rt_ssize_t rt_hpm_eth_read(rt_device_t dev, rt_off_t pos, void * buffer, rt_size_t size)
 {
     return 0;
 }
 
-static rt_size_t rt_hpm_eth_write(rt_device_t dev, rt_off_t pos, const void * buffer, rt_size_t size)
+static rt_ssize_t rt_hpm_eth_write(rt_device_t dev, rt_off_t pos, const void * buffer, rt_size_t size)
 {
     return 0;
 }

bsp/hpmicro/libraries/drivers/drv_i2c.c

@@ -55,7 +55,7 @@ static struct hpm_i2c hpm_i2cs[] =
 #endif
 };
 
-static rt_size_t hpm_i2c_master_transfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num);
+static rt_ssize_t hpm_i2c_master_transfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num);
 
 
 struct rt_i2c_bus_device_ops hpm_i2c_ops =
@@ -65,7 +65,7 @@ struct rt_i2c_bus_device_ops hpm_i2c_ops =
     RT_NULL
 };
 
-static rt_size_t hpm_i2c_master_transfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t hpm_i2c_master_transfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     RT_ASSERT(bus != RT_NULL);
     RT_ASSERT(msgs != RT_NULL);

bsp/hpmicro/libraries/drivers/drv_i2s.c

@@ -24,7 +24,7 @@
 #include "drv_i2s.h"
 #include "drivers/audio.h"
 
-static rt_size_t hpm_i2s_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size);
+static rt_ssize_t hpm_i2s_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size);
 
 struct hpm_i2s
 {
@@ -462,7 +462,7 @@ static rt_err_t hpm_i2s_stop(struct rt_audio_device* audio, int stream)
     return RT_EOK;
 }
 
-static rt_size_t hpm_i2s_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
+static rt_ssize_t hpm_i2s_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
 {
     RT_ASSERT(audio != RT_NULL);
     struct hpm_i2s* hpm_audio = (struct hpm_i2s*)audio->parent.user_data;

bsp/hpmicro/libraries/drivers/drv_rtc.c

@@ -25,8 +25,8 @@
 static rt_err_t hpm_rtc_init(rt_device_t dev);
 static rt_err_t hpm_rtc_open(rt_device_t dev, rt_uint16_t oflag);
 static rt_err_t hpm_rtc_close(rt_device_t dev);
-static rt_size_t hpm_rtc_read(rt_device_t dev, rt_off_t pos, void *buf, rt_size_t size);
-static rt_size_t hpm_rtc_write(rt_device_t dev, rt_off_t pos, const void *buf, rt_size_t size);
+static rt_ssize_t hpm_rtc_read(rt_device_t dev, rt_off_t pos, void *buf, rt_size_t size);
+static rt_ssize_t hpm_rtc_write(rt_device_t dev, rt_off_t pos, const void *buf, rt_size_t size);
 static rt_err_t hpm_rtc_control(rt_device_t dev, int cmd, void *args);
 
 static time_t hpm_rtc_get_timestamp(void);
@@ -64,11 +64,11 @@ static rt_err_t hpm_rtc_close(rt_device_t dev)
 {
     return RT_EOK;
 }
-static rt_size_t hpm_rtc_read(rt_device_t dev, rt_off_t pos, void *buf, rt_size_t size)
+static rt_ssize_t hpm_rtc_read(rt_device_t dev, rt_off_t pos, void *buf, rt_size_t size)
 {
     return 0;
 }
-static rt_size_t hpm_rtc_write(rt_device_t dev, rt_off_t pos, const void *buf, rt_size_t size)
+static rt_ssize_t hpm_rtc_write(rt_device_t dev, rt_off_t pos, const void *buf, rt_size_t size)
 {
     return 0;
 }

bsp/hpmicro/libraries/drivers/drv_uart_v2.c

@@ -864,7 +864,7 @@ static int hpm_uart_getc(struct rt_serial_device *serial)
     return result;
 }
 
-static rt_size_t hpm_uart_transmit(struct rt_serial_device *serial,
+static rt_ssize_t hpm_uart_transmit(struct rt_serial_device *serial,
                                     rt_uint8_t *buf,
                                     rt_size_t size,
                                     rt_uint32_t tx_flag)

bsp/hpmicro/libraries/drivers/drv_usb.c

@@ -13,8 +13,8 @@
 /* Definition of logic unit number for each drive */
 #define LUN_USB     (0U)    /* lun 0 of usb drive */
 
-static rt_size_t hpm_usb_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size);
-static rt_size_t hpm_usb_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size);
+static rt_ssize_t hpm_usb_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size);
+static rt_ssize_t hpm_usb_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size);
 rt_err_t  hpm_usb_control(rt_device_t dev, int cmd, void *args);
 
 rt_uint8_t usb_dev_addr;
@@ -50,7 +50,7 @@ void hpm_usb_set_addr(uint8_t dev_addr)
     usb_dev_addr = dev_addr;
 }
 
-static rt_size_t hpm_usb_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t hpm_usb_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_bool_t result;
 
@@ -63,7 +63,7 @@ static rt_size_t hpm_usb_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_si
     return result ? size : 0;
 }
 
-static rt_size_t hpm_usb_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t hpm_usb_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     bool result;
 

bsp/imx6sx/cortex-a9/drivers/emac_drv.c

@@ -116,13 +116,13 @@ static rt_err_t imx_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t imx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t imx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t imx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t imx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/imxrt/libraries/drivers/drv_eth.c

@@ -489,14 +489,14 @@ static rt_err_t rt_imxrt_eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_imxrt_eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_imxrt_eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     dbg_log(DBG_LOG, "rt_imxrt_eth_read...\n");
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_imxrt_eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_imxrt_eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     dbg_log(DBG_LOG, "rt_imxrt_eth_write...\n");
     rt_set_errno(-RT_ENOSYS);

bsp/imxrt/libraries/drivers/drv_i2c.c

@@ -134,10 +134,10 @@ static struct imxrt_i2c_bus lpi2c6 =
 
 #if (defined(BSP_USING_I2C1) || defined(BSP_USING_I2C2) || defined(BSP_USING_I2C3) || defined(BSP_USING_I2C4) ||defined(BSP_USING_I2C5) || defined(BSP_USING_I2C6))
 
-static rt_size_t imxrt_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t imxrt_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num);
-static rt_size_t imxrt_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t imxrt_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num);
 static rt_err_t imxrt_i2c_bus_control(struct rt_i2c_bus_device *bus,
@@ -249,7 +249,7 @@ static status_t LPI2C_MasterWaitForTxFifoAllEmpty(LPI2C_Type *base)
     return kStatus_Success;
 }
 
-static rt_size_t imxrt_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t imxrt_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num)
 {
@@ -365,7 +365,7 @@ static rt_size_t imxrt_i2c_mst_xfer(struct rt_i2c_bus_device *bus,
     return i;
 }
 
-static rt_size_t imxrt_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t imxrt_i2c_slv_xfer(struct rt_i2c_bus_device *bus,
                                     struct rt_i2c_msg msgs[],
                                     rt_uint32_t num)
 {

bsp/imxrt/libraries/drivers/drv_mdio.c

@@ -51,7 +51,7 @@ static rt_bool_t rt_hw_mdio_init(void *bus, rt_uint32_t src_clock_hz)
     return RT_TRUE;
 }
 
-static rt_size_t rt_hw_mdio_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t rt_hw_mdio_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     RT_ASSERT(data);
     struct rt_mdio_bus *bus_obj = (struct rt_mdio_bus *)bus;
@@ -96,7 +96,7 @@ static rt_size_t rt_hw_mdio_read(void *bus, rt_uint32_t addr, rt_uint32_t reg, v
 }
 
 
-static rt_size_t rt_hw_mdio_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
+static rt_ssize_t rt_hw_mdio_write(void *bus, rt_uint32_t addr, rt_uint32_t reg, void *data, rt_uint32_t size)
 {
     struct rt_mdio_bus *bus_obj = (struct rt_mdio_bus *)bus;
     uint32_t counter;

bsp/imxrt/libraries/drivers/drv_rtc.c

@@ -103,12 +103,12 @@ static rt_err_t imxrt_hp_rtc_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t imxrt_hp_rtc_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t imxrt_hp_rtc_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     return -RT_EINVAL;
 }
 
-static rt_size_t imxrt_hp_rtc_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t imxrt_hp_rtc_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     return -RT_EINVAL;
 }

bsp/imxrt/libraries/drivers/drv_sai.c

@@ -504,7 +504,7 @@ static rt_err_t imxrt_payer_stop(struct rt_audio_device* audio, int stream)
     return RT_EOK;
 
 }
-static rt_size_t imxrt_payer_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
+static rt_ssize_t imxrt_payer_transmit(struct rt_audio_device* audio, const void* writeBuf, void* readBuf, rt_size_t size)
 {
     RT_ASSERT(audio != RT_NULL);
 #if defined (BSP_USING_AUDIO_RECORD)

bsp/imxrt/libraries/drivers/drv_usbd.c

@@ -152,7 +152,7 @@ static rt_err_t _ehci0_ep_disable(uep_t ep)
     return RT_EOK;
 }
 
-static rt_size_t _ehci0_ep_read(rt_uint8_t address, void *buffer)
+static rt_ssize_t _ehci0_ep_read(rt_uint8_t address, void *buffer)
 {
     rt_size_t size = 0;
 
@@ -161,13 +161,13 @@ static rt_size_t _ehci0_ep_read(rt_uint8_t address, void *buffer)
     return size;
 }
 
-static rt_size_t _ehci0_ep_read_prepare(rt_uint8_t address, void *buffer, rt_size_t size)
+static rt_ssize_t _ehci0_ep_read_prepare(rt_uint8_t address, void *buffer, rt_size_t size)
 {
     USB_DeviceRecvRequest(ehci0_handle, address, buffer, size);
     return size;
 }
 
-static rt_size_t _ehci0_ep_write(rt_uint8_t address, void *buffer, rt_size_t size)
+static rt_ssize_t _ehci0_ep_write(rt_uint8_t address, void *buffer, rt_size_t size)
 {
     USB_DeviceSendRequest(ehci0_handle, address, buffer, size);
     return size;

bsp/juicevm/driver/drv_uart.c

@@ -24,7 +24,7 @@ static rt_err_t  uart_configure(struct rt_serial_device *serial, struct serial_c
 static rt_err_t  uart_control(struct rt_serial_device *serial, int cmd, void *arg);
 static int       uart_putc(struct rt_serial_device *serial, char c);
 static int       uart_getc(struct rt_serial_device *serial);
-static rt_size_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
+static rt_ssize_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction);
 
 void UART0_DriverIRQHandler(void);
 
@@ -115,7 +115,7 @@ static int uart_getc(struct rt_serial_device *serial)
     return ch;
 }
 
-static rt_size_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
+static rt_ssize_t uart_dma_transmit(struct rt_serial_device *serial, rt_uint8_t *buf, rt_size_t size, int direction)
 {
     return (0);
 }

bsp/k210/drivers/drv_lcd.c

@@ -443,7 +443,7 @@ static rt_err_t drv_lcd_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t drv_lcd_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t drv_lcd_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
 
     /* Not need */
@@ -451,7 +451,7 @@ static rt_size_t drv_lcd_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_si
     return 0;
 }
 
-static rt_size_t drv_lcd_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t drv_lcd_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
 
     /* Not need */

bsp/lm3s8962/drivers/sdcard.c

@@ -691,7 +691,7 @@ static rt_err_t rt_sdcard_close(rt_device_t dev)
 	return RT_EOK;
 }
 
-static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
 	DRESULT status;
 
@@ -705,7 +705,7 @@ static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
 	return size;
 }
 
-static rt_size_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 	DRESULT status;
 

bsp/lm3s8962/drivers/serial.c

@@ -188,7 +188,7 @@ static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
 	return RT_EOK;
 }
 
-static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
 	rt_uint8_t* ptr;
 	struct rt_lm3s_serial *serial = (struct rt_lm3s_serial*)dev;
@@ -248,7 +248,7 @@ static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
 	return (rt_size_t)ptr - (rt_size_t)buffer;
 }
 
-static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 	struct rt_lm3s_serial* serial;
 	char *ptr;

bsp/lm3s9b9x/drivers/sdcard.c

@@ -691,7 +691,7 @@ static rt_err_t rt_sdcard_close(rt_device_t dev)
 	return RT_EOK;
 }
 
-static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
 	DRESULT status;
 
@@ -705,7 +705,7 @@ static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
 	return size;
 }
 
-static rt_size_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 	DRESULT status;
 

bsp/lm3s9b9x/drivers/serial.c

@@ -188,7 +188,7 @@ static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
 	return RT_EOK;
 }
 
-static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
 	rt_uint8_t* ptr;
 	struct rt_lm3s_serial *serial = (struct rt_lm3s_serial*)dev;
@@ -248,7 +248,7 @@ static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
 	return (rt_size_t)ptr - (rt_size_t)buffer;
 }
 
-static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 	struct rt_lm3s_serial* serial;
 	char *ptr;

bsp/lm4f232/drivers/serial.c

@@ -188,7 +188,7 @@ static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
 	return RT_EOK;
 }
 
-static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
 	rt_uint8_t* ptr;
 	struct rt_lm3s_serial *serial = (struct rt_lm3s_serial*)dev;
@@ -248,7 +248,7 @@ static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
 	return (rt_size_t)ptr - (rt_size_t)buffer;
 }
 
-static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
 	struct rt_lm3s_serial* serial;
 	char *ptr;

bsp/loongson/ls1cdev/drivers/drv_rtc.c

@@ -84,7 +84,7 @@ static rt_err_t rt_rtc_open(rt_device_t dev, rt_uint16_t oflag)
     return RT_EOK;
 }
 
-static rt_size_t rt_rtc_read(
+static rt_ssize_t rt_rtc_read(
     rt_device_t     dev,
     rt_off_t        pos,
     void*           buffer,

bsp/loongson/ls1cdev/drivers/net/synopGMAC.c

@@ -403,13 +403,13 @@ static rt_err_t eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/loongson/ls2kdev/drivers/ata/dwc_ahsata.c

@@ -1197,13 +1197,13 @@ int dwc_ahsata_probe(struct rt_device *dev)
     return dwc_ahci_start_ports(uc_priv);
 }
 
-rt_size_t dwc_ahsata_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+rt_ssize_t dwc_ahsata_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     struct blk_device *blk = (struct blk_device *)dev;
     return sata_read_common(blk->ahci_device, blk, pos, size, buffer);
 }
 
-rt_size_t dwc_ahsata_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+rt_ssize_t dwc_ahsata_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     struct blk_device *blk = (struct blk_device *)dev;
     return sata_write_common(blk->ahci_device, blk, pos, size, buffer);

bsp/loongson/ls2kdev/drivers/ata/dwc_ahsata.h

@@ -18,8 +18,8 @@ int dwc_ahsata_bus_reset(struct rt_device *dev);
 int dwc_ahsata_probe(struct rt_device *dev);
 int dwc_ahsata_scan(struct rt_device *dev);
 int dwc_ahsata_port_status(struct rt_device *dev, int port);
-rt_size_t dwc_ahsata_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size);
-rt_size_t dwc_ahsata_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size);
+rt_ssize_t dwc_ahsata_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size);
+rt_ssize_t dwc_ahsata_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size);
 rt_err_t dwc_ahsata_control(rt_device_t dev, int cmd, void *args);
 
 #endif

bsp/loongson/ls2kdev/drivers/drv_rtc.c

@@ -108,7 +108,7 @@ static rt_err_t rt_rtc_open(rt_device_t dev, rt_uint16_t oflag)
     return RT_EOK;
 }
 
-static rt_size_t rt_rtc_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_rtc_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     return 0;
 }

bsp/loongson/ls2kdev/drivers/net/synopGMAC.c

@@ -423,13 +423,13 @@ static rt_err_t eth_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t eth_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t eth_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/lpc176x/drivers/emac.c

@@ -342,16 +342,14 @@ static rt_err_t lpc17xx_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t lpc17xx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t lpc17xx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
-static rt_size_t lpc17xx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t lpc17xx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
 static rt_err_t lpc17xx_emac_control(rt_device_t dev, int cmd, void *args)

bsp/lpc176x/drivers/sd.c

@@ -438,7 +438,7 @@ static rt_err_t rt_sdcard_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     bool status;
 
@@ -450,7 +450,7 @@ static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_
     return 0;
 }
 
-static rt_size_t rt_sdcard_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     bool status;
 

bsp/lpc176x/drivers/uart.c

@@ -203,7 +203,7 @@ static rt_err_t rt_uart_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_uart_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_uint8_t *ptr;
     struct rt_uart_lpc *uart = (struct rt_uart_lpc *)dev;
@@ -250,7 +250,7 @@ static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_si
     return 0;
 }
 
-static rt_size_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     char *ptr;
     ptr = (char *)buffer;

bsp/lpc178x/drivers/emac.c

@@ -366,16 +366,14 @@ static rt_err_t lpc17xx_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t lpc17xx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t lpc17xx_emac_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
-static rt_size_t lpc17xx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t lpc17xx_emac_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
-    rt_set_errno(-RT_ENOSYS);
-    return 0;
+    return -RT_ENOSYS;
 }
 
 static rt_err_t lpc17xx_emac_control(rt_device_t dev, int cmd, void *args)

bsp/lpc178x/drivers/uart.c

@@ -220,7 +220,7 @@ static rt_err_t rt_uart_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_uart_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;
     struct rt_uart_lpc *uart = (struct rt_uart_lpc*)dev;
@@ -267,7 +267,7 @@ static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_si
     return 0;
 }
 
-static rt_size_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     struct rt_uart_lpc *uart = (struct rt_uart_lpc*)dev;
     char *ptr;

bsp/lpc2148/drivers/dm9000.c

@@ -60,13 +60,13 @@ static rt_err_t rt_dm9000_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_dm9000_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_dm9000_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t rt_dm9000_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_dm9000_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/lpc2148/drivers/sd.c

@@ -30,7 +30,7 @@ static rt_err_t rt_sdcard_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     /* append partition offset */
     pos += part.offset * 512;
@@ -38,7 +38,7 @@ static rt_size_t rt_sdcard_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
     return 0;
 }
 
-static rt_size_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_sdcard_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     /* append partition offset */
     pos += part.offset * 512;

bsp/lpc2148/drivers/serial.c

@@ -190,7 +190,7 @@ static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
     return RT_EOK;
 }
 
-static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;
     struct rt_lpcserial *lpc_serial = (struct rt_lpcserial*)dev;
@@ -252,7 +252,7 @@ static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
     return (rt_size_t)ptr - (rt_size_t)buffer;
 }
 
-static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     struct rt_lpcserial* lpc_serial;
     char *ptr;

bsp/lpc2478/drivers/serial.c

@@ -163,7 +163,7 @@ static rt_err_t rt_serial_control(rt_device_t dev, int cmd, void *args)
     return RT_EOK;
 }
 
-static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
 {
     rt_uint8_t* ptr;
     struct rt_lpcserial *lpc_serial = (struct rt_lpcserial*)dev;
@@ -225,7 +225,7 @@ static rt_size_t rt_serial_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_
     return (rt_size_t)ptr - (rt_size_t)buffer;
 }
 
-static rt_size_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+static rt_ssize_t rt_serial_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
 {
     struct rt_lpcserial* lpc_serial;
     char *ptr;

bsp/lpc408x/drivers/drv_emac.c

@@ -334,13 +334,13 @@ static rt_err_t lpc_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/lpc408x/drivers/drv_led.c

@@ -61,7 +61,7 @@ static rt_err_t rt_led_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
+static rt_ssize_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
                              rt_size_t size)
 {
     rt_ubase_t index = 0;
@@ -86,7 +86,7 @@ static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
     return index;
 }
 
-static rt_size_t rt_led_write(rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_led_write(rt_device_t dev, rt_off_t pos,
                               const void *buffer, rt_size_t size)
 {
     rt_ubase_t index = 0;

bsp/lpc43xx/drivers/drv_emac.c

@@ -355,13 +355,13 @@ static rt_err_t lpc_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/lpc43xx/drivers/drv_led.c

@@ -76,7 +76,7 @@ static rt_err_t rt_led_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
+static rt_ssize_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
                              rt_size_t size)
 {
     rt_ubase_t index = 0;
@@ -101,7 +101,7 @@ static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
     return index;
 }
 
-static rt_size_t rt_led_write(rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_led_write(rt_device_t dev, rt_off_t pos,
                               const void *buffer, rt_size_t size)
 {
     rt_ubase_t index = 0;

bsp/lpc5410x/drivers/drv_led.c

@@ -61,7 +61,7 @@ static rt_err_t rt_led_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
+static rt_ssize_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
                              rt_size_t size)
 {
     rt_ubase_t index = 0;
@@ -86,7 +86,7 @@ static rt_size_t rt_led_read(rt_device_t dev, rt_off_t pos, void *buffer,
     return index;
 }
 
-static rt_size_t rt_led_write(rt_device_t dev, rt_off_t pos,
+static rt_ssize_t rt_led_write(rt_device_t dev, rt_off_t pos,
                               const void *buffer, rt_size_t size)
 {
     rt_ubase_t index = 0;

bsp/lpc54114-lite/drivers/audio/drv_sound.c

@@ -297,7 +297,7 @@ static rt_err_t lpc_audio_configure(struct rt_audio_device *audio, struct rt_aud
     return result;
 }
 
-static rt_size_t lpc_audio_transmit(struct rt_audio_device *audio, const void *writeBuf, void *readBuf, rt_size_t size)
+static rt_ssize_t lpc_audio_transmit(struct rt_audio_device *audio, const void *writeBuf, void *readBuf, rt_size_t size)
 {
     RT_ASSERT(audio != RT_NULL);
     i2s_transfer_t transfer;

bsp/lpc54114-lite/drivers/drv_i2c.c

@@ -33,7 +33,7 @@ static uint32_t get_i2c_freq(I2C_Type *base)
     return freq;
 }
 
-static rt_size_t master_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t master_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     rt_size_t ret = (0);
 
@@ -82,7 +82,7 @@ static rt_size_t master_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg ms
     return ret;
 }
 
-static rt_size_t slave_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
+static rt_ssize_t slave_xfer(struct rt_i2c_bus_device *bus, struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     return 0;
 }

bsp/lpc54608-LPCXpresso/drivers/drv_emac.c

@@ -383,13 +383,13 @@ static rt_err_t lpc_emac_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;
 }
 
-static rt_size_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t lpc_emac_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_set_errno(-RT_ENOSYS);
     return 0;

bsp/lpc54608-LPCXpresso/drivers/drv_i2c.c

@@ -143,7 +143,7 @@ struct lpc_i2c_bus
     I2C_Type *I2C;
 };
 
-static rt_size_t lpc_i2c_xfer(struct rt_i2c_bus_device *bus,
+static rt_ssize_t lpc_i2c_xfer(struct rt_i2c_bus_device *bus,
                               struct rt_i2c_msg msgs[], rt_uint32_t num)
 {
     struct rt_i2c_msg *msg;

bsp/lpc54608-LPCXpresso/drivers/drv_sd.c

@@ -34,7 +34,7 @@ static rt_err_t rt_mci_close(rt_device_t dev)
     return RT_EOK;
 }
 
-static rt_size_t rt_mci_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
+static rt_ssize_t rt_mci_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
 {
     rt_uint8_t status = kStatus_Success;
     struct mci_device *mci = (struct mci_device *)dev;
@@ -67,7 +67,7 @@ static rt_size_t rt_mci_read(rt_device_t dev, rt_off_t pos, void *buffer, rt_siz
     return 0;
 }
 
-static rt_size_t rt_mci_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
+static rt_ssize_t rt_mci_write(rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
 {
     rt_uint8_t status = kStatus_Success;
     struct mci_device *mci = (struct mci_device *)dev;