spi: atmel: use managed resource for gpio chip select
Use the managed gpio CS pin request so that we avoid having trouble
in the cleanup code.
In fact, if module was configured with DT, cleanup code released
invalid pin. Since resource wasn't freed, module cannot be reinserted.
This require to extract the gpio request call from the "setup" function
and call it in the appropriate probe function.
Reported-by: Alexander Morozov <linux@meltdown.ru>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8feac59..d3affa6 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -24,6 +24,7 @@
#include <linux/io.h>
#include <linux/gpio.h>
+#include <linux/of_gpio.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
@@ -1204,7 +1205,6 @@
u32 csr;
unsigned int bits = spi->bits_per_word;
unsigned int npcs_pin;
- int ret;
as = spi_master_get_devdata(spi->master);
@@ -1247,16 +1247,9 @@
if (!asd)
return -ENOMEM;
- if (as->use_cs_gpios) {
- ret = gpio_request(npcs_pin, dev_name(&spi->dev));
- if (ret) {
- kfree(asd);
- return ret;
- }
-
+ if (as->use_cs_gpios)
gpio_direction_output(npcs_pin,
!(spi->mode & SPI_CS_HIGH));
- }
asd->npcs_pin = npcs_pin;
spi->controller_state = asd;
@@ -1471,13 +1464,11 @@
static void atmel_spi_cleanup(struct spi_device *spi)
{
struct atmel_spi_device *asd = spi->controller_state;
- unsigned gpio = (unsigned long) spi->controller_data;
if (!asd)
return;
spi->controller_state = NULL;
- gpio_free(gpio);
kfree(asd);
}
@@ -1499,6 +1490,39 @@
}
/*-------------------------------------------------------------------------*/
+static int atmel_spi_gpio_cs(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct atmel_spi *as = spi_master_get_devdata(master);
+ struct device_node *np = master->dev.of_node;
+ int i;
+ int ret = 0;
+ int nb = 0;
+
+ if (!as->use_cs_gpios)
+ return 0;
+
+ if (!np)
+ return 0;
+
+ nb = of_gpio_named_count(np, "cs-gpios");
+ for (i = 0; i < nb; i++) {
+ int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+ "cs-gpios", i);
+
+ if (cs_gpio == -EPROBE_DEFER)
+ return cs_gpio;
+
+ if (gpio_is_valid(cs_gpio)) {
+ ret = devm_gpio_request(&pdev->dev, cs_gpio,
+ dev_name(&pdev->dev));
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
static int atmel_spi_probe(struct platform_device *pdev)
{
@@ -1577,6 +1601,10 @@
master->num_chipselect = 4;
}
+ ret = atmel_spi_gpio_cs(pdev);
+ if (ret)
+ goto out_unmap_regs;
+
as->use_dma = false;
as->use_pdc = false;
if (as->caps.has_dma_support) {