Commit 1bcc0879 authored by Ajay Singh's avatar Ajay Singh Committed by Kalle Valo
Browse files

wilc1000: add reset/terminate/repeat command support for SPI bus 



Add reset/terminate/repeat command for SPI module. In case of SPI commands
failure, the host should issue a RESET command to WILC chip to recover
from any temporary bus error.
For now, the new command support is added and later the SPI read/write
API's would be modified to make use of these commands for retry mechanism

Signed-off-by: default avatarAjay Singh <ajay.kathat@microchip.com>
Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210916164902.74629-6-ajay.kathat@microchip.com
parent 5bb9de8b

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

+61 −0
Original line number Diff line number Diff line
@@ -144,6 +144,12 @@ struct wilc_spi_rsp_data { 
	u8 data[];

} __packed;



struct wilc_spi_special_cmd_rsp {

	u8 skip_byte;

	u8 rsp_cmd_type;

	u8 status;

} __packed;



static int wilc_bus_probe(struct spi_device *spi)

{

	int ret;
@@ -709,6 +715,61 @@ static int wilc_spi_dma_rw(struct wilc *wilc, u8 cmd, u32 adr, u8 *b, u32 sz) 
	return 0;

}



static int wilc_spi_special_cmd(struct wilc *wilc, u8 cmd)

{

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

	struct wilc_spi *spi_priv = wilc->bus_data;

	u8 wb[32], rb[32];

	int cmd_len, resp_len = 0;

	struct wilc_spi_cmd *c;

	struct wilc_spi_special_cmd_rsp *r;



	if (cmd != CMD_TERMINATE && cmd != CMD_REPEAT && cmd != CMD_RESET)

		return -EINVAL;



	memset(wb, 0x0, sizeof(wb));

	memset(rb, 0x0, sizeof(rb));

	c = (struct wilc_spi_cmd *)wb;

	c->cmd_type = cmd;



	if (cmd == CMD_RESET)

		memset(c->u.simple_cmd.addr, 0xFF, 3);



	cmd_len = offsetof(struct wilc_spi_cmd, u.simple_cmd.crc);

	resp_len = sizeof(*r);



	if (spi_priv->crc7_enabled) {

		c->u.simple_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);

		cmd_len += 1;

	}

	if (cmd_len + resp_len > ARRAY_SIZE(wb)) {

		dev_err(&spi->dev, "spi buffer size too small (%d) (%d) (%zu)\n",

			cmd_len, resp_len, ARRAY_SIZE(wb));

		return -EINVAL;

	}



	if (wilc_spi_tx_rx(wilc, wb, rb, cmd_len + resp_len)) {

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

		return -EINVAL;

	}



	r = (struct wilc_spi_special_cmd_rsp *)&rb[cmd_len];

	if (r->rsp_cmd_type != cmd) {

		if (!spi_priv->probing_crc)

			dev_err(&spi->dev,

				"Failed cmd response, cmd (%02x), resp (%02x)\n",

				cmd, r->rsp_cmd_type);

		return -EINVAL;

	}



	if (r->status != WILC_SPI_COMMAND_STAT_SUCCESS) {

		dev_err(&spi->dev, "Failed cmd state response state (%02x)\n",

			r->status);

		return -EINVAL;

	}

	return 0;

}



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

{

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