bcm63xx arch resets the SPI controller at early boot. However, bmips arch
needs to perform a reset when probing the driver.
Signed-off-by: Álvaro Fernández Rojas <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
---
v2: use devm_reset_control_get_exclusive
drivers/spi/spi-bcm63xx.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/spi/spi-bcm63xx.c b/drivers/spi/spi-bcm63xx.c
index 0f1b10a4ef0c..8ab04affaf7b 100644
--- a/drivers/spi/spi-bcm63xx.c
+++ b/drivers/spi/spi-bcm63xx.c
@@ -18,6 +18,7 @@
#include <linux/err.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
+#include <linux/reset.h>
/* BCM 6338/6348 SPI core */
#define SPI_6348_RSET_SIZE 64
@@ -493,6 +494,7 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
struct bcm63xx_spi *bs;
int ret;
u32 num_cs = BCM63XX_SPI_MAX_CS;
+ struct reset_control *reset;
if (dev->of_node) {
const struct of_device_id *match;
@@ -529,6 +531,15 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
return PTR_ERR(clk);
}
+ reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(reset)) {
+ ret = PTR_ERR(reset);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev,
+ "failed to get reset controller: %d\n", ret);
+ return ret;
+ }
+
master = spi_alloc_master(dev, sizeof(*bs));
if (!master) {
dev_err(dev, "out of memory\n");
@@ -579,6 +590,12 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
if (ret)
goto out_err;
+ ret = reset_control_reset(reset);
+ if (ret) {
+ dev_err(dev, "unable to reset device: %d\n", ret);
+ goto out_clk_disable;
+ }
+
bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
/* register and we are done */
--
2.27.0
On 6/15/2020 2:09 AM, Álvaro Fernández Rojas wrote:
> bcm63xx arch resets the SPI controller at early boot. However, bmips arch
> needs to perform a reset when probing the driver.
>
> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
> Reviewed-by: Philipp Zabel <[email protected]>
> ---
> v2: use devm_reset_control_get_exclusive
>
> drivers/spi/spi-bcm63xx.c | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/drivers/spi/spi-bcm63xx.c b/drivers/spi/spi-bcm63xx.c
> index 0f1b10a4ef0c..8ab04affaf7b 100644
> --- a/drivers/spi/spi-bcm63xx.c
> +++ b/drivers/spi/spi-bcm63xx.c
> @@ -18,6 +18,7 @@
> #include <linux/err.h>
> #include <linux/pm_runtime.h>
> #include <linux/of.h>
> +#include <linux/reset.h>
>
> /* BCM 6338/6348 SPI core */
> #define SPI_6348_RSET_SIZE 64
> @@ -493,6 +494,7 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
> struct bcm63xx_spi *bs;
> int ret;
> u32 num_cs = BCM63XX_SPI_MAX_CS;
> + struct reset_control *reset;
>
> if (dev->of_node) {
> const struct of_device_id *match;
> @@ -529,6 +531,15 @@ static int bcm63xx_spi_probe(struct platform_device *pdev)
> return PTR_ERR(clk);
> }
>
> + reset = devm_reset_control_get_exclusive(dev, NULL);
> + if (IS_ERR(reset)) {
> + ret = PTR_ERR(reset);
> + if (ret != -EPROBE_DEFER)
> + dev_err(dev,
> + "failed to get reset controller: %d\n", ret);
> + return ret;
> + }
This should be devm_reset_control_get_exclusive_optional() for a number
of reasons the first one being the most important as it reflects reality
of the HW:
- not all BCM63xx platforms have a dedicated reset line for the SPI
controller (like the ARM-based SoCs)
- until you also update all Device Tree sources to have a 'resets'
property in their SPI controller node, this is likely going to be failing
This also applies to patch 3.
--
Florian