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authorLinus Torvalds2015-04-13 15:05:40 -0700
committerLinus Torvalds2015-04-13 15:05:40 -0700
commit0055dc5b23cc1738fc2f14221cf922a83057d8fb (patch)
tree791ace137da6784403804b15cd8195fd51a1a4a0 /drivers/spi/spi-dw.c
parent1b57c7c2fbb81763cd4a6940c8530c98022c409c (diff)
parent56afdb70ca9140cdcbdcf01870f3e4e2e8be17f5 (diff)
Merge tag 'spi-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown: "Only one framework update this time around, a change from Lars-Peter to move full to pm_ops and remove the legacy bus PM ops. Otherwise it's all driver updates: - make the spidev driver complain loudly if registered as spidev with DT rather than with a compatible string, hopefully helping people avoid making that mistake. - error handling and robustness fixes for the Designware and Intel MID drivers from Andy Shevchenko. - substantial performance improvements for the Raspberry Pi driver from Martin Sperl. - several new features for spidev_test from Adrian Remonda and Ian Abbott" * tag 'spi-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (75 commits) spi: bcm2835: enabling polling mode for transfers shorter than 30us spi: bcm2835: transform native-cs to gpio-cs on first spi_setup spi: img-spfi: Control CS lines with GPIO spi: img-spfi: Reset controller after each message spi: img-spfi: Implement a handle_err() callback spi: img-spfi: Setup TRANSACTION register before CONTROL register spi: Make master->handle_err() callback optional to avoid crashes spi: img-spfi: Limit bit clock to 1/4th of input clock spi: img-spfi: Implement a prepare_message() callback spi: fsl-dspi: Add ~50ns delay between cs and sck spi: fsl-dspi: Add cs-sck delays spi: fsl-dspi: Fix clock rate scale values spi: signedness bug in qspi_trigger_transfer_out_int() spi: imx: read back the RX/TX watermark levels earlier spi: spi-bfin5xx: Initialize cr_width in bfin_spi_pump_transfers() spi: bitbang: only toggle bitchanges spi: pxa2xx: missing break in pxa2xx_ssp_get_clk_div() spi: fsl-dspi: Fix clock rate scale values spi: Using Trigger number to transmit/receive data spi: bcm2835: fill FIFO before enabling interrupts to reduce interrupts/message ...
Diffstat (limited to 'drivers/spi/spi-dw.c')
-rw-r--r--drivers/spi/spi-dw.c306
1 files changed, 92 insertions, 214 deletions
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index 4847afba89f4..8d67d03c71eb 100644
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -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;
@@ -143,13 +138,26 @@ 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 && 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)
{
u32 tx_left, tx_room, rxtx_gap;
tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
- tx_room = dws->fifo_len - dw_readw(dws, DW_SPI_TXFLR);
+ tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR);
/*
* Another concern is about the tx/rx mismatch, we
@@ -170,7 +178,7 @@ static inline u32 rx_max(struct dw_spi *dws)
{
u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
- return min_t(u32, rx_left, dw_readw(dws, DW_SPI_RXFLR));
+ return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR));
}
static void dw_writer(struct dw_spi *dws)
@@ -186,7 +194,7 @@ static void dw_writer(struct dw_spi *dws)
else
txw = *(u16 *)(dws->tx);
}
- dw_writew(dws, DW_SPI_DR, txw);
+ dw_writel(dws, DW_SPI_DR, txw);
dws->tx += dws->n_bytes;
}
}
@@ -197,7 +205,7 @@ static void dw_reader(struct dw_spi *dws)
u16 rxw;
while (max--) {
- rxw = dw_readw(dws, DW_SPI_DR);
+ rxw = dw_readl(dws, DW_SPI_DR);
/* Care rx only if the transfer's original "rx" is not null */
if (dws->rx_end - dws->len) {
if (dws->n_bytes == 1)
@@ -209,103 +217,22 @@ 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)
-{
- if (!dws->cur_msg->is_dma_mapped
- || !dws->dma_inited
- || !dws->cur_chip->enable_dma
- || !dws->dma_ops)
- return 0;
-
- if (dws->cur_transfer->tx_dma)
- dws->tx_dma = dws->cur_transfer->tx_dma;
-
- if (dws->cur_transfer->rx_dma)
- dws->rx_dma = dws->cur_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)
{
- /* Stop the hw */
- spi_enable_chip(dws, 0);
+ 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);
+ u16 irq_status = dw_readl(dws, DW_SPI_ISR);
/* Error handling */
if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
- dw_readw(dws, DW_SPI_TXOICR);
- dw_readw(dws, DW_SPI_RXOICR);
- dw_readw(dws, DW_SPI_RXUICR);
+ dw_readl(dws, DW_SPI_ICR);
int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
return IRQ_HANDLED;
}
@@ -313,7 +240,7 @@ 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) {
@@ -328,13 +255,14 @@ 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;
- u16 irq_status = dw_readw(dws, DW_SPI_ISR) & 0x3f;
+ struct spi_master *master = dev_id;
+ struct dw_spi *dws = spi_master_get_devdata(master);
+ u16 irq_status = dw_readl(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;
}
@@ -343,7 +271,7 @@ 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);
@@ -351,64 +279,32 @@ 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;
- u8 bits = 0;
+ struct dw_spi *dws = spi_master_get_devdata(master);
+ struct chip_data *chip = spi_get_ctldata(spi);
u8 imask = 0;
- u8 cs_change = 0;
- u16 txint_level = 0;
+ u16 txlevel = 0;
u16 clk_div = 0;
u32 speed = 0;
u32 cr0 = 0;
+ int ret;
- /* 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->dma_mapped = 0;
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;
dws->tx = (void *)transfer->tx_buf;
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;
- if (chip != dws->prev_chip)
- cs_change = 1;
+ dws->len = transfer->len;
+
+ spi_enable_chip(dws, 0);
cr0 = chip->cr0;
@@ -416,32 +312,37 @@ static void pump_transfers(unsigned long data)
if (transfer->speed_hz) {
speed = chip->speed_hz;
- if ((transfer->speed_hz != speed) || (!chip->clk_div)) {
+ if ((transfer->speed_hz != speed) || !chip->clk_div) {
speed = transfer->speed_hz;
/* clk_div doesn't support odd number */
- clk_div = dws->max_freq / speed;
- clk_div = (clk_div + 1) & 0xfffe;
+ clk_div = (dws->max_freq / speed + 1) & 0xfffe;
chip->speed_hz = speed;
chip->clk_div = clk_div;
+
+ spi_set_clk(dws, chip->clk_div);
}
}
if (transfer->bits_per_word) {
- bits = transfer->bits_per_word;
- dws->n_bytes = dws->dma_width = bits >> 3;
- cr0 = (bits - 1)
+ if (transfer->bits_per_word == 8) {
+ dws->n_bytes = 1;
+ dws->dma_width = 1;
+ } else if (transfer->bits_per_word == 16) {
+ dws->n_bytes = 2;
+ dws->dma_width = 2;
+ }
+ cr0 = (transfer->bits_per_word - 1)
| (chip->type << SPI_FRF_OFFSET)
| (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)
@@ -453,80 +354,60 @@ static void pump_transfers(unsigned long data)
cr0 |= (chip->tmode << SPI_TMOD_OFFSET);
}
+ dw_writel(dws, DW_SPI_CTRL0, cr0);
+
/* Check if current transfer is a DMA transaction */
- dws->dma_mapped = map_dma_buffers(dws);
+ if (master->can_dma && master->can_dma(master, spi, transfer))
+ dws->dma_mapped = master->cur_msg_mapped;
+
+ /* For poll mode just disable all interrupts */
+ spi_mask_intr(dws, 0xff);
/*
* Interrupt mode
* we only need set the TXEI IRQ, as TX/RX always happen syncronizely
*/
- if (!dws->dma_mapped && !chip->poll_mode) {
- int templen = dws->len / dws->n_bytes;
-
- txint_level = dws->fifo_len / 2;
- txint_level = (templen > txint_level) ? txint_level : templen;
+ if (dws->dma_mapped) {
+ ret = dws->dma_ops->dma_setup(dws, transfer);
+ if (ret < 0) {
+ spi_enable_chip(dws, 1);
+ return ret;
+ }
+ } else if (!chip->poll_mode) {
+ txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);
+ dw_writel(dws, DW_SPI_TXFLTR, txlevel);
+ /* Set the interrupt mask */
imask |= SPI_INT_TXEI | SPI_INT_TXOI |
SPI_INT_RXUI | SPI_INT_RXOI;
+ spi_umask_intr(dws, imask);
+
dws->transfer_handler = interrupt_transfer;
}
- /*
- * Reprogram registers only if
- * 1. chip select changes
- * 2. clk_div is changed
- * 3. control value changes
- */
- if (dw_readw(dws, DW_SPI_CTRL0) != cr0 || cs_change || clk_div || imask) {
- spi_enable_chip(dws, 0);
-
- if (dw_readw(dws, DW_SPI_CTRL0) != cr0)
- dw_writew(dws, DW_SPI_CTRL0, cr0);
-
- spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
- spi_chip_sel(dws, spi, 1);
-
- /* Set the interrupt mask, for poll mode just disable all int */
- spi_mask_intr(dws, 0xff);
- if (imask)
- spi_umask_intr(dws, imask);
- if (txint_level)
- dw_writew(dws, DW_SPI_TXFLTR, txint_level);
+ spi_enable_chip(dws, 1);
- spi_enable_chip(dws, 1);
- if (cs_change)
- dws->prev_chip = chip;
+ if (dws->dma_mapped) {
+ ret = dws->dma_ops->dma_transfer(dws, transfer);
+ if (ret < 0)
+ return ret;
}
- if (dws->dma_mapped)
- 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);
+ if (dws->dma_mapped)
+ dws->dma_ops->dma_stop(dws);
- return 0;
+ spi_reset_chip(dws);
}
/* This may be called twice for each spi dev */
@@ -561,8 +442,6 @@ static int dw_spi_setup(struct spi_device *spi)
chip->rx_threshold = 0;
chip->tx_threshold = 0;
-
- chip->enable_dma = chip_info->enable_dma;
}
if (spi->bits_per_word == 8) {
@@ -610,9 +489,7 @@ static void dw_spi_cleanup(struct spi_device *spi)
/* Restart the controller, disable all interrupts, clean rx fifo */
static void spi_hw_init(struct device *dev, struct dw_spi *dws)
{
- spi_enable_chip(dws, 0);
- spi_mask_intr(dws, 0xff);
- spi_enable_chip(dws, 1);
+ spi_reset_chip(dws);
/*
* Try to detect the FIFO depth if not set by interface driver,
@@ -622,11 +499,11 @@ static void spi_hw_init(struct device *dev, struct dw_spi *dws)
u32 fifo;
for (fifo = 1; fifo < 256; fifo++) {
- dw_writew(dws, DW_SPI_TXFLTR, fifo);
- if (fifo != dw_readw(dws, DW_SPI_TXFLTR))
+ dw_writel(dws, DW_SPI_TXFLTR, fifo);
+ if (fifo != dw_readl(dws, DW_SPI_TXFLTR))
break;
}
- dw_writew(dws, DW_SPI_TXFLTR, 0);
+ dw_writel(dws, DW_SPI_TXFLTR, 0);
dws->fifo_len = (fifo == 1) ? 0 : fifo;
dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len);
@@ -646,13 +523,12 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
dws->master = master;
dws->type = SSI_MOTO_SPI;
- dws->prev_chip = NULL;
dws->dma_inited = 0;
dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
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;
@@ -664,7 +540,9 @@ 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;
@@ -676,11 +554,11 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
if (ret) {
dev_warn(dev, "DMA init failed\n");
dws->dma_inited = 0;
+ } else {
+ master->can_dma = dws->dma_ops->can_dma;
}
}
- 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) {