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-rw-r--r--drivers/spi/spi-sh-msiof.c66
1 files changed, 59 insertions, 7 deletions
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 9bdc292..8aa5c7b 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -19,6 +19,7 @@
#include <linux/dmaengine.h>
#include <linux/err.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
@@ -55,6 +56,7 @@ struct sh_msiof_spi_priv {
void *rx_dma_page;
dma_addr_t tx_dma_addr;
dma_addr_t rx_dma_addr;
+ unsigned short unused_ss;
bool native_cs_inited;
bool native_cs_high;
bool slave_aborted;
@@ -547,8 +549,8 @@ static int sh_msiof_spi_setup(struct spi_device *spi)
spi->cs_gpio = (uintptr_t)spi->controller_data;
}
- if (spi->cs_gpio >= 0) {
- gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
+ if (gpio_is_valid(spi->cs_gpio)) {
+ gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
return 0;
}
@@ -580,14 +582,20 @@ static int sh_msiof_prepare_message(struct spi_master *master,
{
struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
const struct spi_device *spi = msg->spi;
+ u32 ss, cs_high;
/* Configure pins before asserting CS */
- sh_msiof_spi_set_pin_regs(p, spi->chip_select,
- !!(spi->mode & SPI_CPOL),
+ if (gpio_is_valid(spi->cs_gpio)) {
+ ss = p->unused_ss;
+ cs_high = p->native_cs_high;
+ } else {
+ ss = spi->chip_select;
+ cs_high = !!(spi->mode & SPI_CS_HIGH);
+ }
+ sh_msiof_spi_set_pin_regs(p, ss, !!(spi->mode & SPI_CPOL),
!!(spi->mode & SPI_CPHA),
!!(spi->mode & SPI_3WIRE),
- !!(spi->mode & SPI_LSB_FIRST),
- !!(spi->mode & SPI_CS_HIGH));
+ !!(spi->mode & SPI_LSB_FIRST), cs_high);
return 0;
}
@@ -1091,6 +1099,45 @@ static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
}
#endif
+static int sh_msiof_get_cs_gpios(struct sh_msiof_spi_priv *p)
+{
+ struct device *dev = &p->pdev->dev;
+ unsigned int used_ss_mask = 0;
+ unsigned int cs_gpios = 0;
+ unsigned int num_cs, i;
+ int ret;
+
+ ret = gpiod_count(dev, "cs");
+ if (ret <= 0)
+ return 0;
+
+ num_cs = max_t(unsigned int, ret, p->master->num_chipselect);
+ for (i = 0; i < num_cs; i++) {
+ struct gpio_desc *gpiod;
+
+ gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS);
+ if (!IS_ERR(gpiod)) {
+ cs_gpios++;
+ continue;
+ }
+
+ if (PTR_ERR(gpiod) != -ENOENT)
+ return PTR_ERR(gpiod);
+
+ if (i >= MAX_SS) {
+ dev_err(dev, "Invalid native chip select %d\n", i);
+ return -EINVAL;
+ }
+ used_ss_mask |= BIT(i);
+ }
+ p->unused_ss = ffz(used_ss_mask);
+ if (cs_gpios && p->unused_ss >= MAX_SS) {
+ dev_err(dev, "No unused native chip select available\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
{
@@ -1304,13 +1351,18 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
if (p->info->rx_fifo_override)
p->rx_fifo_size = p->info->rx_fifo_override;
+ /* Setup GPIO chip selects */
+ master->num_chipselect = p->info->num_chipselect;
+ ret = sh_msiof_get_cs_gpios(p);
+ if (ret)
+ goto err1;
+
/* init master code */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
master->flags = chipdata->master_flags;
master->bus_num = pdev->id;
master->dev.of_node = pdev->dev.of_node;
- master->num_chipselect = p->info->num_chipselect;
master->setup = sh_msiof_spi_setup;
master->prepare_message = sh_msiof_prepare_message;
master->slave_abort = sh_msiof_slave_abort;
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