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authorLinus Walleij <linus.walleij@linaro.org>2019-12-05 10:24:11 +0100
committerMark Brown <broonie@kernel.org>2019-12-27 01:08:11 +0000
commitf03ee2042b2dc46e3452e87324d90f147de4a944 (patch)
tree3c551c002e6f4b604cfdf645e999954cea93b227 /drivers/spi
parent28d1dddc59f6b7fc085093e7c1e978b33f0caf4c (diff)
spi: oc-tiny: Use GPIO descriptors
Switch the OC Tiny driver over to handling CS GPIOs using GPIO descriptors in the core. This driver is entirely relying on GPIOs to be used for chipselect, so let the core pick these out using either device tree or machine descriptors. There are no in-tree users of this driver so no board files need to be patched, out-of-tree boardfiles can use machine descriptor tables, c.f. commit 1dfbf334f123. Cc: Thomas Chou <thomas@wytron.com.tw> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20191205092411.64341-1-linus.walleij@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/spi-oc-tiny.c50
1 files changed, 1 insertions, 49 deletions
diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c
index e2331eb7b47a..9df7c5979c29 100644
--- a/drivers/spi/spi-oc-tiny.c
+++ b/drivers/spi/spi-oc-tiny.c
@@ -20,7 +20,6 @@
#include <linux/spi/spi_bitbang.h>
#include <linux/spi/spi_oc_tiny.h>
#include <linux/io.h>
-#include <linux/gpio.h>
#include <linux/of.h>
#define DRV_NAME "spi_oc_tiny"
@@ -50,8 +49,6 @@ struct tiny_spi {
unsigned int txc, rxc;
const u8 *txp;
u8 *rxp;
- int gpio_cs_count;
- int *gpio_cs;
};
static inline struct tiny_spi *tiny_spi_to_hw(struct spi_device *sdev)
@@ -66,16 +63,6 @@ static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz)
return min(DIV_ROUND_UP(hw->freq, hz * 2), (1U << hw->baudwidth)) - 1;
}
-static void tiny_spi_chipselect(struct spi_device *spi, int is_active)
-{
- struct tiny_spi *hw = tiny_spi_to_hw(spi);
-
- if (hw->gpio_cs_count > 0) {
- gpio_set_value(hw->gpio_cs[spi->chip_select],
- (spi->mode & SPI_CS_HIGH) ? is_active : !is_active);
- }
-}
-
static int tiny_spi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
@@ -203,24 +190,10 @@ static int tiny_spi_of_probe(struct platform_device *pdev)
{
struct tiny_spi *hw = platform_get_drvdata(pdev);
struct device_node *np = pdev->dev.of_node;
- unsigned int i;
u32 val;
if (!np)
return 0;
- hw->gpio_cs_count = of_gpio_count(np);
- if (hw->gpio_cs_count > 0) {
- hw->gpio_cs = devm_kcalloc(&pdev->dev,
- hw->gpio_cs_count, sizeof(unsigned int),
- GFP_KERNEL);
- if (!hw->gpio_cs)
- return -ENOMEM;
- }
- for (i = 0; i < hw->gpio_cs_count; i++) {
- hw->gpio_cs[i] = of_get_gpio_flags(np, i, NULL);
- if (hw->gpio_cs[i] < 0)
- return -ENODEV;
- }
hw->bitbang.master->dev.of_node = pdev->dev.of_node;
if (!of_property_read_u32(np, "clock-frequency", &val))
hw->freq = val;
@@ -240,7 +213,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
struct tiny_spi_platform_data *platp = dev_get_platdata(&pdev->dev);
struct tiny_spi *hw;
struct spi_master *master;
- unsigned int i;
int err = -ENODEV;
master = spi_alloc_master(&pdev->dev, sizeof(struct tiny_spi));
@@ -249,9 +221,9 @@ static int tiny_spi_probe(struct platform_device *pdev)
/* setup the master state. */
master->bus_num = pdev->id;
- master->num_chipselect = 255;
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
master->setup = tiny_spi_setup;
+ master->use_gpio_descriptors = true;
hw = spi_master_get_devdata(master);
platform_set_drvdata(pdev, hw);
@@ -259,7 +231,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
/* setup the state for the bitbang driver */
hw->bitbang.master = master;
hw->bitbang.setup_transfer = tiny_spi_setup_transfer;
- hw->bitbang.chipselect = tiny_spi_chipselect;
hw->bitbang.txrx_bufs = tiny_spi_txrx_bufs;
/* find and map our resources */
@@ -279,12 +250,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
}
/* find platform data */
if (platp) {
- hw->gpio_cs_count = platp->gpio_cs_count;
- hw->gpio_cs = platp->gpio_cs;
- if (platp->gpio_cs_count && !platp->gpio_cs) {
- err = -EBUSY;
- goto exit;
- }
hw->freq = platp->freq;
hw->baudwidth = platp->baudwidth;
} else {
@@ -292,13 +257,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
if (err)
goto exit;
}
- for (i = 0; i < hw->gpio_cs_count; i++) {
- err = gpio_request(hw->gpio_cs[i], dev_name(&pdev->dev));
- if (err)
- goto exit_gpio;
- gpio_direction_output(hw->gpio_cs[i], 1);
- }
- hw->bitbang.master->num_chipselect = max(1, hw->gpio_cs_count);
/* register our spi controller */
err = spi_bitbang_start(&hw->bitbang);
@@ -308,9 +266,6 @@ static int tiny_spi_probe(struct platform_device *pdev)
return 0;
-exit_gpio:
- while (i-- > 0)
- gpio_free(hw->gpio_cs[i]);
exit:
spi_master_put(master);
return err;
@@ -320,11 +275,8 @@ static int tiny_spi_remove(struct platform_device *pdev)
{
struct tiny_spi *hw = platform_get_drvdata(pdev);
struct spi_master *master = hw->bitbang.master;
- unsigned int i;
spi_bitbang_stop(&hw->bitbang);
- for (i = 0; i < hw->gpio_cs_count; i++)
- gpio_free(hw->gpio_cs[i]);
spi_master_put(master);
return 0;
}