Commit 6fd879f9 authored by Amisha Patel's avatar Amisha Patel Committed by Kalle Valo
Browse files

wifi: wilc1000: add SPI commands retry mechanism 



In some situations like, chip wake-up with powersave enabled, SPI
commands are failing temporarily. Reissuing commands after reset helps
to overcome the failure. So, add the retry limit and reset command
sequence API for read/write SPI commands.

Signed-off-by: default avatarAmisha Patel <amisha.patel@microchip.com>
Signed-off-by: default avatarKalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230724163955.4583-1-amisha.patel@microchip.com
parent 11958528

drivers/net/wireless/microchip/wilc1000/spi.c

+103 −45
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ static int wilc_spi_reset(struct wilc *wilc); 
#define CMD_SINGLE_READ				0xca

#define CMD_RESET				0xcf



#define SPI_RETRY_MAX_LIMIT			10

#define SPI_ENABLE_VMM_RETRY_LIMIT		2



/* SPI response fields (section 11.1.2 in ATWILC1000 User Guide): */
@@ -830,59 +831,91 @@ static int wilc_spi_special_cmd(struct wilc *wilc, u8 cmd) 
	return 0;

}



static void wilc_spi_reset_cmd_sequence(struct wilc *wl, u8 attempt, u32 addr)

{

	struct spi_device *spi = to_spi_device(wl->dev);

	struct wilc_spi *spi_priv = wl->bus_data;



	if (!spi_priv->probing_crc)

		dev_err(&spi->dev, "Reset and retry %d %x\n", attempt, addr);



	usleep_range(1000, 1100);

	wilc_spi_reset(wl);

	usleep_range(1000, 1100);

}



static int wilc_spi_read_reg(struct wilc *wilc, u32 addr, u32 *data)

{

	struct spi_device *spi = to_spi_device(wilc->dev);

	int result;

	u8 cmd = CMD_SINGLE_READ;

	u8 clockless = 0;

	u8 i;



	if (addr < WILC_SPI_CLOCKLESS_ADDR_LIMIT) {

	if (addr <= WILC_SPI_CLOCKLESS_ADDR_LIMIT) {

		/* Clockless register */

		cmd = CMD_INTERNAL_READ;

		clockless = 1;

	}



	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_single_read(wilc, cmd, addr, data, clockless);

	if (result) {

		dev_err(&spi->dev, "Failed cmd, read reg (%08x)...\n", addr);

		return result;

		if (!result) {

			le32_to_cpus(data);

			return 0;

		}



	le32_to_cpus(data);

		/* retry is not applicable for clockless registers */

		if (clockless)

			break;



	return 0;

		dev_err(&spi->dev, "Failed cmd, read reg (%08x)...\n", addr);

		wilc_spi_reset_cmd_sequence(wilc, i, addr);

	}



	return result;

}



static int wilc_spi_read(struct wilc *wilc, u32 addr, u8 *buf, u32 size)

{

	struct spi_device *spi = to_spi_device(wilc->dev);

	int result;

	u8 i;



	if (size <= 4)

		return -EINVAL;



	result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_READ, addr, buf, size);

	if (result) {

	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_READ, addr,

					 buf, size);

		if (!result)

			return 0;



		dev_err(&spi->dev, "Failed cmd, read block (%08x)...\n", addr);

		return result;



		wilc_spi_reset_cmd_sequence(wilc, i, addr);

	}



	return 0;

	return result;

}



static int spi_internal_write(struct wilc *wilc, u32 adr, u32 dat)

{

	struct spi_device *spi = to_spi_device(wilc->dev);

	int result;

	u8 i;



	result = wilc_spi_write_cmd(wilc, CMD_INTERNAL_WRITE, adr, dat, 0);

	if (result) {

	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_write_cmd(wilc, CMD_INTERNAL_WRITE, adr,

					    dat, 0);

		if (!result)

			return 0;

		dev_err(&spi->dev, "Failed internal write cmd...\n");

		return result;



		wilc_spi_reset_cmd_sequence(wilc, i, adr);

	}



	return 0;

	return result;

}



static int spi_internal_read(struct wilc *wilc, u32 adr, u32 *data)
@@ -890,17 +923,22 @@ static int spi_internal_read(struct wilc *wilc, u32 adr, u32 *data) 
	struct spi_device *spi = to_spi_device(wilc->dev);

	struct wilc_spi *spi_priv = wilc->bus_data;

	int result;

	u8 i;



	result = wilc_spi_single_read(wilc, CMD_INTERNAL_READ, adr, data, 0);

	if (result) {

	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_single_read(wilc, CMD_INTERNAL_READ, adr,

					      data, 0);

		if (!result) {

			le32_to_cpus(data);

			return 0;

		}

		if (!spi_priv->probing_crc)

			dev_err(&spi->dev, "Failed internal read cmd...\n");

		return result;

	}



	le32_to_cpus(data);

		wilc_spi_reset_cmd_sequence(wilc, i, adr);

	}



	return 0;

	return result;

}



/********************************************
@@ -915,20 +953,27 @@ static int wilc_spi_write_reg(struct wilc *wilc, u32 addr, u32 data) 
	int result;

	u8 cmd = CMD_SINGLE_WRITE;

	u8 clockless = 0;

	u8 i;



	if (addr < WILC_SPI_CLOCKLESS_ADDR_LIMIT) {

	if (addr <= WILC_SPI_CLOCKLESS_ADDR_LIMIT) {

		/* Clockless register */

		cmd = CMD_INTERNAL_WRITE;

		clockless = 1;

	}



	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_write_cmd(wilc, cmd, addr, data, clockless);

	if (result) {

		if (!result)

			return 0;



		dev_err(&spi->dev, "Failed cmd, write reg (%08x)...\n", addr);

		return result;

	}



	return 0;

		if (clockless)

			break;



		wilc_spi_reset_cmd_sequence(wilc, i, addr);

	}

	return result;

}



static int spi_data_rsp(struct wilc *wilc, u8 cmd)
@@ -981,6 +1026,7 @@ static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size) 
{

	struct spi_device *spi = to_spi_device(wilc->dev);

	int result;

	u8 i;



	/*

	 * has to be greated than 4
@@ -988,11 +1034,14 @@ static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size) 
	if (size <= 4)

		return -EINVAL;



	result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_WRITE, addr, NULL, size);

	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {

		result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_WRITE, addr,

					 NULL, size);

		if (result) {

			dev_err(&spi->dev,

				"Failed cmd, write block (%08x)...\n", addr);

		return result;

			wilc_spi_reset_cmd_sequence(wilc, i, addr);

			continue;

		}



		/*
@@ -1001,13 +1050,22 @@ static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size) 
		result = spi_data_write(wilc, buf, size);

		if (result) {

			dev_err(&spi->dev, "Failed block data write...\n");

		return result;

			wilc_spi_reset_cmd_sequence(wilc, i, addr);

			continue;

		}



		/*

		 * Data response

		 */

	return spi_data_rsp(wilc, CMD_DMA_EXT_WRITE);

		result = spi_data_rsp(wilc, CMD_DMA_EXT_WRITE);

		if (result) {

			dev_err(&spi->dev, "Failed block data rsp...\n");

			wilc_spi_reset_cmd_sequence(wilc, i, addr);

			continue;

		}

		break;

	}

	return result;

}



/********************************************