Add support to be able to specify the delay to be introduced b/w
power and reset lines on power up sequence. With this, the driver
could also be used by other WiFi chips (e.g. WILC1000/WILC3000
devices that need a delay of 5ms b/w power and reset line for
a proper powering up sequence).
Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---
drivers/mmc/core/pwrseq_sd8787.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/pwrseq_sd8787.c b/drivers/mmc/core/pwrseq_sd8787.c
index 68a826f1c0a1..a554eefdf1b1 100644
--- a/drivers/mmc/core/pwrseq_sd8787.c
+++ b/drivers/mmc/core/pwrseq_sd8787.c
@@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/module.h>
+#include <linux/property.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -27,6 +28,7 @@ struct mmc_pwrseq_sd8787 {
struct mmc_pwrseq pwrseq;
struct gpio_desc *reset_gpio;
struct gpio_desc *pwrdn_gpio;
+ u32 reset_pwrdwn_delay_ms;
};
#define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787, pwrseq)
@@ -37,7 +39,7 @@ static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
- msleep(300);
+ msleep(pwrseq->reset_pwrdwn_delay_ms);
gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
}
@@ -64,6 +66,7 @@ static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
{
struct mmc_pwrseq_sd8787 *pwrseq;
struct device *dev = &pdev->dev;
+ int ret;
pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
if (!pwrseq)
@@ -77,6 +80,12 @@ static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
if (IS_ERR(pwrseq->reset_gpio))
return PTR_ERR(pwrseq->reset_gpio);
+ ret = device_property_read_u32(dev, "reset-power-delay-ms",
+ &pwrseq->reset_pwrdwn_delay_ms);
+ /* Keep compatibility with old devices. */
+ if (ret)
+ pwrseq->reset_pwrdwn_delay_ms = 300;
+
pwrseq->pwrseq.dev = dev;
pwrseq->pwrseq.ops = &mmc_pwrseq_sd8787_ops;
pwrseq->pwrseq.owner = THIS_MODULE;
--
2.25.1
