Commit c22c62db authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Mark Brown
Browse files

spi: dw: move to SPI core message handling 



This patch removes a lot of duplicate code since SPI core provides a nice
message handling.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 3e00803a

drivers/spi/spi-dw-mid.c

+2 −2
Original line number Diff line number Diff line
@@ -110,7 +110,7 @@ static void dw_spi_dma_tx_done(void *arg) 


	if (test_and_clear_bit(TX_BUSY, &dws->dma_chan_busy) & BIT(RX_BUSY))

		return;

	dw_spi_xfer_done(dws);

	spi_finalize_current_transfer(dws->master);

}



static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws)
@@ -155,7 +155,7 @@ static void dw_spi_dma_rx_done(void *arg) 


	if (test_and_clear_bit(RX_BUSY, &dws->dma_chan_busy) & BIT(TX_BUSY))

		return;

	dw_spi_xfer_done(dws);

	spi_finalize_current_transfer(dws->master);

}



static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws)

drivers/spi/spi-dw.c

+47 −136
Original line number Diff line number Diff line
@@ -28,11 +28,6 @@ 
#include <linux/debugfs.h>

#endif



#define START_STATE	((void *)0)

#define RUNNING_STATE	((void *)1)

#define DONE_STATE	((void *)2)

#define ERROR_STATE	((void *)-1)



/* Slave spi_dev related */

struct chip_data {

	u16 cr0;
@@ -143,6 +138,19 @@ static inline void dw_spi_debugfs_remove(struct dw_spi *dws) 
}

#endif /* CONFIG_DEBUG_FS */



static void dw_spi_set_cs(struct spi_device *spi, bool enable)

{

	struct dw_spi *dws = spi_master_get_devdata(spi->master);

	struct chip_data *chip = spi_get_ctldata(spi);



	/* Chip select logic is inverted from spi_set_cs() */

	if (chip->cs_control)

		chip->cs_control(!enable);



	if (!enable)

		dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select));

}



/* Return the max entries we can fill into tx fifo */

static inline u32 tx_max(struct dw_spi *dws)

{
@@ -209,93 +217,41 @@ static void dw_reader(struct dw_spi *dws) 
	}

}



static void *next_transfer(struct dw_spi *dws)

{

	struct spi_message *msg = dws->cur_msg;

	struct spi_transfer *trans = dws->cur_transfer;



	/* Move to next transfer */

	if (trans->transfer_list.next != &msg->transfers) {

		dws->cur_transfer =

			list_entry(trans->transfer_list.next,

					struct spi_transfer,

					transfer_list);

		return RUNNING_STATE;

	}



	return DONE_STATE;

}



/*

 * Note: first step is the protocol driver prepares

 * a dma-capable memory, and this func just need translate

 * the virt addr to physical

 */

static int map_dma_buffers(struct dw_spi *dws)

static int map_dma_buffers(struct spi_master *master,

		struct spi_device *spi, struct spi_transfer *transfer)

{

	if (!dws->cur_msg->is_dma_mapped

	struct dw_spi *dws = spi_master_get_devdata(master);

	struct chip_data *chip = spi_get_ctldata(spi);



	if (!master->cur_msg->is_dma_mapped

		|| !dws->dma_inited

		|| !dws->cur_chip->enable_dma

		|| !chip->enable_dma

		|| !dws->dma_ops)

		return 0;



	if (dws->cur_transfer->tx_dma)

		dws->tx_dma = dws->cur_transfer->tx_dma;

	if (transfer->tx_dma)

		dws->tx_dma = transfer->tx_dma;



	if (dws->cur_transfer->rx_dma)

		dws->rx_dma = dws->cur_transfer->rx_dma;

	if (transfer->rx_dma)

		dws->rx_dma = transfer->rx_dma;



	return 1;

}



/* Caller already set message->status; dma and pio irqs are blocked */

static void giveback(struct dw_spi *dws)

{

	struct spi_transfer *last_transfer;

	struct spi_message *msg;



	msg = dws->cur_msg;

	dws->cur_msg = NULL;

	dws->cur_transfer = NULL;

	dws->prev_chip = dws->cur_chip;

	dws->cur_chip = NULL;

	dws->dma_mapped = 0;



	last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,

					transfer_list);



	if (!last_transfer->cs_change)

		spi_chip_sel(dws, msg->spi, 0);



	spi_finalize_current_message(dws->master);

}



static void int_error_stop(struct dw_spi *dws, const char *msg)

{

	spi_reset_chip(dws);



	dev_err(&dws->master->dev, "%s\n", msg);

	dws->cur_msg->state = ERROR_STATE;

	tasklet_schedule(&dws->pump_transfers);

	dws->master->cur_msg->status = -EIO;

	spi_finalize_current_transfer(dws->master);

}



void dw_spi_xfer_done(struct dw_spi *dws)

{

	/* Update total byte transferred return count actual bytes read */

	dws->cur_msg->actual_length += dws->len;



	/* Move to next transfer */

	dws->cur_msg->state = next_transfer(dws);



	/* Handle end of message */

	if (dws->cur_msg->state == DONE_STATE) {

		dws->cur_msg->status = 0;

		giveback(dws);

	} else

		tasklet_schedule(&dws->pump_transfers);

}

EXPORT_SYMBOL_GPL(dw_spi_xfer_done);



static irqreturn_t interrupt_transfer(struct dw_spi *dws)

{

	u16 irq_status = dw_readw(dws, DW_SPI_ISR);
@@ -312,7 +268,7 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws) 
	dw_reader(dws);

	if (dws->rx_end == dws->rx) {

		spi_mask_intr(dws, SPI_INT_TXEI);

		dw_spi_xfer_done(dws);

		spi_finalize_current_transfer(dws->master);

		return IRQ_HANDLED;

	}

	if (irq_status & SPI_INT_TXEI) {
@@ -327,13 +283,14 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws) 


static irqreturn_t dw_spi_irq(int irq, void *dev_id)

{

	struct dw_spi *dws = dev_id;

	struct spi_master *master = dev_id;

	struct dw_spi *dws = spi_master_get_devdata(master);

	u16 irq_status = dw_readw(dws, DW_SPI_ISR) & 0x3f;



	if (!irq_status)

		return IRQ_NONE;



	if (!dws->cur_msg) {

	if (!master->cur_msg) {

		spi_mask_intr(dws, SPI_INT_TXEI);

		return IRQ_HANDLED;

	}
@@ -342,7 +299,7 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) 
}



/* Must be called inside pump_transfers() */

static void poll_transfer(struct dw_spi *dws)

static int poll_transfer(struct dw_spi *dws)

{

	do {

		dw_writer(dws);
@@ -350,17 +307,14 @@ static void poll_transfer(struct dw_spi *dws) 
		cpu_relax();

	} while (dws->rx_end > dws->rx);



	dw_spi_xfer_done(dws);

	return 0;

}



static void pump_transfers(unsigned long data)

static int dw_spi_transfer_one(struct spi_master *master,

		struct spi_device *spi, struct spi_transfer *transfer)

{

	struct dw_spi *dws = (struct dw_spi *)data;

	struct spi_message *message = NULL;

	struct spi_transfer *transfer = NULL;

	struct spi_transfer *previous = NULL;

	struct spi_device *spi = NULL;

	struct chip_data *chip = NULL;

	struct dw_spi *dws = spi_master_get_devdata(master);

	struct chip_data *chip = spi_get_ctldata(spi);

	u8 bits = 0;

	u8 imask = 0;

	u8 cs_change = 0;
@@ -369,35 +323,8 @@ static void pump_transfers(unsigned long data) 
	u32 speed = 0;

	u32 cr0 = 0;



	/* Get current state information */

	message = dws->cur_msg;

	transfer = dws->cur_transfer;

	chip = dws->cur_chip;

	spi = message->spi;



	if (message->state == ERROR_STATE) {

		message->status = -EIO;

		goto early_exit;

	}



	/* Handle end of message */

	if (message->state == DONE_STATE) {

		message->status = 0;

		goto early_exit;

	}



	/* Delay if requested at end of transfer */

	if (message->state == RUNNING_STATE) {

		previous = list_entry(transfer->transfer_list.prev,

					struct spi_transfer,

					transfer_list);

		if (previous->delay_usecs)

			udelay(previous->delay_usecs);

	}



	dws->n_bytes = chip->n_bytes;

	dws->dma_width = chip->dma_width;

	dws->cs_control = chip->cs_control;



	dws->rx_dma = transfer->rx_dma;

	dws->tx_dma = transfer->tx_dma;
@@ -405,7 +332,7 @@ static void pump_transfers(unsigned long data) 
	dws->tx_end = dws->tx + transfer->len;

	dws->rx = transfer->rx_buf;

	dws->rx_end = dws->rx + transfer->len;

	dws->len = dws->cur_transfer->len;

	dws->len = transfer->len;

	if (chip != dws->prev_chip)

		cs_change = 1;
@@ -437,13 +364,12 @@ static void pump_transfers(unsigned long data) 
			| (spi->mode << SPI_MODE_OFFSET)

			| (chip->tmode << SPI_TMOD_OFFSET);

	}

	message->state = RUNNING_STATE;



	/*

	 * Adjust transfer mode if necessary. Requires platform dependent

	 * chipselect mechanism.

	 */

	if (dws->cs_control) {

	if (chip->cs_control) {

		if (dws->rx && dws->tx)

			chip->tmode = SPI_TMOD_TR;

		else if (dws->rx)
@@ -456,10 +382,9 @@ static void pump_transfers(unsigned long data) 
	}



	dw_writew(dws, DW_SPI_CTRL0, cr0);

	spi_chip_sel(dws, spi, 1);



	/* Check if current transfer is a DMA transaction */

	dws->dma_mapped = map_dma_buffers(dws);

	dws->dma_mapped = map_dma_buffers(master, spi, transfer);



	/* For poll mode just disable all interrupts */

	spi_mask_intr(dws, 0xff);
@@ -489,31 +414,17 @@ static void pump_transfers(unsigned long data) 
		dws->dma_ops->dma_transfer(dws, cs_change);



	if (chip->poll_mode)

		poll_transfer(dws);



	return;

		return poll_transfer(dws);



early_exit:

	giveback(dws);

	return 1;

}



static int dw_spi_transfer_one_message(struct spi_master *master,

static void dw_spi_handle_err(struct spi_master *master,

		struct spi_message *msg)

{

	struct dw_spi *dws = spi_master_get_devdata(master);



	dws->cur_msg = msg;

	/* Initial message state */

	dws->cur_msg->state = START_STATE;

	dws->cur_transfer = list_entry(dws->cur_msg->transfers.next,

						struct spi_transfer,

						transfer_list);

	dws->cur_chip = spi_get_ctldata(dws->cur_msg->spi);



	/* Launch transfers */

	tasklet_schedule(&dws->pump_transfers);



	return 0;

	spi_reset_chip(dws);

}



/* This may be called twice for each spi dev */
@@ -637,7 +548,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) 
	snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num);



	ret = devm_request_irq(dev, dws->irq, dw_spi_irq, IRQF_SHARED,

			dws->name, dws);

			dws->name, master);

	if (ret < 0) {

		dev_err(&master->dev, "can not get IRQ\n");

		goto err_free_master;
@@ -649,7 +560,9 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) 
	master->num_chipselect = dws->num_cs;

	master->setup = dw_spi_setup;

	master->cleanup = dw_spi_cleanup;

	master->transfer_one_message = dw_spi_transfer_one_message;

	master->set_cs = dw_spi_set_cs;

	master->transfer_one = dw_spi_transfer_one;

	master->handle_err = dw_spi_handle_err;

	master->max_speed_hz = dws->max_freq;

	master->dev.of_node = dev->of_node;
@@ -664,8 +577,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) 
		}

	}



	tasklet_init(&dws->pump_transfers, pump_transfers, (unsigned long)dws);



	spi_master_set_devdata(master, dws);

	ret = devm_spi_register_master(dev, master);

	if (ret) {

drivers/spi/spi-dw.h

+0 −26
Original line number Diff line number Diff line
@@ -96,7 +96,6 @@ struct dw_spi_dma_ops { 


struct dw_spi {

	struct spi_master	*master;

	struct spi_device	*cur_dev;

	enum dw_ssi_type	type;

	char			name[16];
@@ -109,13 +108,7 @@ struct dw_spi { 
	u16			bus_num;

	u16			num_cs;		/* supported slave numbers */



	/* Message Transfer pump */

	struct tasklet_struct	pump_transfers;



	/* Current message transfer state info */

	struct spi_message	*cur_msg;

	struct spi_transfer	*cur_transfer;

	struct chip_data	*cur_chip;

	struct chip_data	*prev_chip;

	size_t			len;

	void			*tx;
@@ -128,10 +121,8 @@ struct dw_spi { 
	size_t			rx_map_len;

	size_t			tx_map_len;

	u8			n_bytes;	/* current is a 1/2 bytes op */

	u8			max_bits_per_word;	/* maxim is 16b */

	u32			dma_width;

	irqreturn_t		(*transfer_handler)(struct dw_spi *dws);

	void			(*cs_control)(u32 command);



	/* Dma info */

	int			dma_inited;
@@ -182,22 +173,6 @@ static inline void spi_set_clk(struct dw_spi *dws, u16 div) 
	dw_writel(dws, DW_SPI_BAUDR, div);

}



static inline void spi_chip_sel(struct dw_spi *dws, struct spi_device *spi,

		int active)

{

	u16 cs = spi->chip_select;

	int gpio_val = active ? (spi->mode & SPI_CS_HIGH) :

		!(spi->mode & SPI_CS_HIGH);



	if (dws->cs_control)

		dws->cs_control(active);

	if (gpio_is_valid(spi->cs_gpio))

		gpio_set_value(spi->cs_gpio, gpio_val);



	if (active)

		dw_writel(dws, DW_SPI_SER, 1 << cs);

}



/* Disable IRQ bits */

static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)

{
@@ -245,7 +220,6 @@ extern int dw_spi_add_host(struct device *dev, struct dw_spi *dws); 
extern void dw_spi_remove_host(struct dw_spi *dws);

extern int dw_spi_suspend_host(struct dw_spi *dws);

extern int dw_spi_resume_host(struct dw_spi *dws);

extern void dw_spi_xfer_done(struct dw_spi *dws);



/* platform related setup */

extern int dw_spi_mid_init(struct dw_spi *dws); /* Intel MID platforms */