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path: root/kernel/drivers/spi/spi-omap2-mcspi.c
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Diffstat (limited to 'kernel/drivers/spi/spi-omap2-mcspi.c')
-rw-r--r--kernel/drivers/spi/spi-omap2-mcspi.c317
1 files changed, 172 insertions, 145 deletions
diff --git a/kernel/drivers/spi/spi-omap2-mcspi.c b/kernel/drivers/spi/spi-omap2-mcspi.c
index d1a5b9fc3..ed8283e73 100644
--- a/kernel/drivers/spi/spi-omap2-mcspi.c
+++ b/kernel/drivers/spi/spi-omap2-mcspi.c
@@ -35,6 +35,7 @@
#include <linux/gcd.h>
#include <linux/spi/spi.h>
+#include <linux/gpio.h>
#include <linux/platform_data/spi-omap2-mcspi.h>
@@ -242,17 +243,37 @@ static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
}
-static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
+static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
u32 l;
- l = mcspi_cached_chconf0(spi);
- if (cs_active)
- l |= OMAP2_MCSPI_CHCONF_FORCE;
- else
- l &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ /* The controller handles the inverted chip selects
+ * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
+ * the inversion from the core spi_set_cs function.
+ */
+ if (spi->mode & SPI_CS_HIGH)
+ enable = !enable;
- mcspi_write_chconf0(spi, l);
+ if (spi->controller_state) {
+ int err = pm_runtime_get_sync(mcspi->dev);
+ if (err < 0) {
+ dev_err(mcspi->dev, "failed to get sync: %d\n", err);
+ return;
+ }
+
+ l = mcspi_cached_chconf0(spi);
+
+ if (enable)
+ l &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ else
+ l |= OMAP2_MCSPI_CHCONF_FORCE;
+
+ mcspi_write_chconf0(spi, l);
+
+ pm_runtime_mark_last_busy(mcspi->dev);
+ pm_runtime_put_autosuspend(mcspi->dev);
+ }
}
static void omap2_mcspi_set_master_mode(struct spi_master *master)
@@ -1003,6 +1024,16 @@ static int omap2_mcspi_setup(struct spi_device *spi)
spi->controller_state = cs;
/* Link this to context save list */
list_add_tail(&cs->node, &ctx->cs);
+
+ if (gpio_is_valid(spi->cs_gpio)) {
+ ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
+ if (ret) {
+ dev_err(&spi->dev, "failed to request gpio\n");
+ return ret;
+ }
+ gpio_direction_output(spi->cs_gpio,
+ !(spi->mode & SPI_CS_HIGH));
+ }
}
if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
@@ -1050,9 +1081,13 @@ static void omap2_mcspi_cleanup(struct spi_device *spi)
mcspi_dma->dma_tx = NULL;
}
}
+
+ if (gpio_is_valid(spi->cs_gpio))
+ gpio_free(spi->cs_gpio);
}
-static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
+static int omap2_mcspi_work_one(struct omap2_mcspi *mcspi,
+ struct spi_device *spi, struct spi_transfer *t)
{
/* We only enable one channel at a time -- the one whose message is
@@ -1062,18 +1097,14 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
* chipselect with the FORCE bit ... CS != channel enable.
*/
- struct spi_device *spi;
- struct spi_transfer *t = NULL;
struct spi_master *master;
struct omap2_mcspi_dma *mcspi_dma;
- int cs_active = 0;
struct omap2_mcspi_cs *cs;
struct omap2_mcspi_device_config *cd;
int par_override = 0;
int status = 0;
u32 chconf;
- spi = m->spi;
master = spi->master;
mcspi_dma = mcspi->dma_channels + spi->chip_select;
cs = spi->controller_state;
@@ -1090,103 +1121,84 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
par_override = 1;
omap2_mcspi_set_enable(spi, 0);
- list_for_each_entry(t, &m->transfers, transfer_list) {
- if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
- status = -EINVAL;
- break;
- }
- if (par_override ||
- (t->speed_hz != spi->max_speed_hz) ||
- (t->bits_per_word != spi->bits_per_word)) {
- par_override = 1;
- status = omap2_mcspi_setup_transfer(spi, t);
- if (status < 0)
- break;
- if (t->speed_hz == spi->max_speed_hz &&
- t->bits_per_word == spi->bits_per_word)
- par_override = 0;
- }
- if (cd && cd->cs_per_word) {
- chconf = mcspi->ctx.modulctrl;
- chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
- mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
- mcspi->ctx.modulctrl =
- mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
- }
+ if (gpio_is_valid(spi->cs_gpio))
+ omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
- if (!cs_active) {
- omap2_mcspi_force_cs(spi, 1);
- cs_active = 1;
- }
-
- chconf = mcspi_cached_chconf0(spi);
- chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
- chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
+ if (par_override ||
+ (t->speed_hz != spi->max_speed_hz) ||
+ (t->bits_per_word != spi->bits_per_word)) {
+ par_override = 1;
+ status = omap2_mcspi_setup_transfer(spi, t);
+ if (status < 0)
+ goto out;
+ if (t->speed_hz == spi->max_speed_hz &&
+ t->bits_per_word == spi->bits_per_word)
+ par_override = 0;
+ }
+ if (cd && cd->cs_per_word) {
+ chconf = mcspi->ctx.modulctrl;
+ chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
+ mcspi->ctx.modulctrl =
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
+ }
- if (t->tx_buf == NULL)
- chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
- else if (t->rx_buf == NULL)
- chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
-
- if (cd && cd->turbo_mode && t->tx_buf == NULL) {
- /* Turbo mode is for more than one word */
- if (t->len > ((cs->word_len + 7) >> 3))
- chconf |= OMAP2_MCSPI_CHCONF_TURBO;
- }
+ chconf = mcspi_cached_chconf0(spi);
+ chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
+ chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
+
+ if (t->tx_buf == NULL)
+ chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
+ else if (t->rx_buf == NULL)
+ chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
+
+ if (cd && cd->turbo_mode && t->tx_buf == NULL) {
+ /* Turbo mode is for more than one word */
+ if (t->len > ((cs->word_len + 7) >> 3))
+ chconf |= OMAP2_MCSPI_CHCONF_TURBO;
+ }
- mcspi_write_chconf0(spi, chconf);
+ mcspi_write_chconf0(spi, chconf);
- if (t->len) {
- unsigned count;
+ if (t->len) {
+ unsigned count;
- if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
- (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
- omap2_mcspi_set_fifo(spi, t, 1);
+ if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
+ (t->len >= DMA_MIN_BYTES))
+ omap2_mcspi_set_fifo(spi, t, 1);
- omap2_mcspi_set_enable(spi, 1);
+ omap2_mcspi_set_enable(spi, 1);
- /* RX_ONLY mode needs dummy data in TX reg */
- if (t->tx_buf == NULL)
- writel_relaxed(0, cs->base
- + OMAP2_MCSPI_TX0);
+ /* RX_ONLY mode needs dummy data in TX reg */
+ if (t->tx_buf == NULL)
+ writel_relaxed(0, cs->base
+ + OMAP2_MCSPI_TX0);
- if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
- (m->is_dma_mapped || t->len >= DMA_MIN_BYTES))
- count = omap2_mcspi_txrx_dma(spi, t);
- else
- count = omap2_mcspi_txrx_pio(spi, t);
- m->actual_length += count;
+ if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
+ (t->len >= DMA_MIN_BYTES))
+ count = omap2_mcspi_txrx_dma(spi, t);
+ else
+ count = omap2_mcspi_txrx_pio(spi, t);
- if (count != t->len) {
- status = -EIO;
- break;
- }
+ if (count != t->len) {
+ status = -EIO;
+ goto out;
}
+ }
- if (t->delay_usecs)
- udelay(t->delay_usecs);
-
- /* ignore the "leave it on after last xfer" hint */
- if (t->cs_change) {
- omap2_mcspi_force_cs(spi, 0);
- cs_active = 0;
- }
+ omap2_mcspi_set_enable(spi, 0);
- omap2_mcspi_set_enable(spi, 0);
+ if (mcspi->fifo_depth > 0)
+ omap2_mcspi_set_fifo(spi, t, 0);
- if (mcspi->fifo_depth > 0)
- omap2_mcspi_set_fifo(spi, t, 0);
- }
+out:
/* Restore defaults if they were overriden */
if (par_override) {
par_override = 0;
status = omap2_mcspi_setup_transfer(spi, NULL);
}
- if (cs_active)
- omap2_mcspi_force_cs(spi, 0);
-
if (cd && cd->cs_per_word) {
chconf = mcspi->ctx.modulctrl;
chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
@@ -1197,78 +1209,91 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
omap2_mcspi_set_enable(spi, 0);
+ if (gpio_is_valid(spi->cs_gpio))
+ omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
+
if (mcspi->fifo_depth > 0 && t)
omap2_mcspi_set_fifo(spi, t, 0);
- m->status = status;
+ return status;
}
-static int omap2_mcspi_transfer_one_message(struct spi_master *master,
- struct spi_message *m)
+static int omap2_mcspi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ struct omap2_mcspi_cs *cs;
+
+ /* Only a single channel can have the FORCE bit enabled
+ * in its chconf0 register.
+ * Scan all channels and disable them except the current one.
+ * A FORCE can remain from a last transfer having cs_change enabled
+ */
+ list_for_each_entry(cs, &ctx->cs, node) {
+ if (msg->spi->controller_state == cs)
+ continue;
+
+ if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
+ cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ writel_relaxed(cs->chconf0,
+ cs->base + OMAP2_MCSPI_CHCONF0);
+ readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
+ }
+ }
+
+ return 0;
+}
+
+static int omap2_mcspi_transfer_one(struct spi_master *master,
+ struct spi_device *spi, struct spi_transfer *t)
{
- struct spi_device *spi;
struct omap2_mcspi *mcspi;
struct omap2_mcspi_dma *mcspi_dma;
- struct spi_transfer *t;
- int status;
+ const void *tx_buf = t->tx_buf;
+ void *rx_buf = t->rx_buf;
+ unsigned len = t->len;
- spi = m->spi;
mcspi = spi_master_get_devdata(master);
mcspi_dma = mcspi->dma_channels + spi->chip_select;
- m->actual_length = 0;
- m->status = 0;
-
- list_for_each_entry(t, &m->transfers, transfer_list) {
- const void *tx_buf = t->tx_buf;
- void *rx_buf = t->rx_buf;
- unsigned len = t->len;
-
- if ((len && !(rx_buf || tx_buf))) {
- dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
- t->speed_hz,
- len,
- tx_buf ? "tx" : "",
- rx_buf ? "rx" : "",
- t->bits_per_word);
- status = -EINVAL;
- goto out;
- }
- if (m->is_dma_mapped || len < DMA_MIN_BYTES)
- continue;
+ if ((len && !(rx_buf || tx_buf))) {
+ dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
+ t->speed_hz,
+ len,
+ tx_buf ? "tx" : "",
+ rx_buf ? "rx" : "",
+ t->bits_per_word);
+ return -EINVAL;
+ }
- if (mcspi_dma->dma_tx && tx_buf != NULL) {
- t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
- len, DMA_TO_DEVICE);
- if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
- dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
- 'T', len);
- status = -EINVAL;
- goto out;
- }
+ if (len < DMA_MIN_BYTES)
+ goto skip_dma_map;
+
+ if (mcspi_dma->dma_tx && tx_buf != NULL) {
+ t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
+ len, DMA_TO_DEVICE);
+ if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
+ dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
+ 'T', len);
+ return -EINVAL;
}
- if (mcspi_dma->dma_rx && rx_buf != NULL) {
- t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
- DMA_FROM_DEVICE);
- if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
- dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
- 'R', len);
- if (tx_buf != NULL)
- dma_unmap_single(mcspi->dev, t->tx_dma,
- len, DMA_TO_DEVICE);
- status = -EINVAL;
- goto out;
- }
+ }
+ if (mcspi_dma->dma_rx && rx_buf != NULL) {
+ t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
+ dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
+ 'R', len);
+ if (tx_buf != NULL)
+ dma_unmap_single(mcspi->dev, t->tx_dma,
+ len, DMA_TO_DEVICE);
+ return -EINVAL;
}
}
- omap2_mcspi_work(mcspi, m);
- /* spi_finalize_current_message() changes the status inside the
- * spi_message, save the status here. */
- status = m->status;
-out:
- spi_finalize_current_message(master);
- return status;
+skip_dma_map:
+ return omap2_mcspi_work_one(mcspi, spi, t);
}
static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
@@ -1347,7 +1372,9 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
master->setup = omap2_mcspi_setup;
master->auto_runtime_pm = true;
- master->transfer_one_message = omap2_mcspi_transfer_one_message;
+ master->prepare_message = omap2_mcspi_prepare_message;
+ master->transfer_one = omap2_mcspi_transfer_one;
+ master->set_cs = omap2_mcspi_set_cs;
master->cleanup = omap2_mcspi_cleanup;
master->dev.of_node = node;
master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;