[PATCH 2/5] mmc: pwrseq_simple: Extend to support more pins
From: Srinivas Kandagatla <hidden>
Date: 2015-01-29 03:14:01
Also in:
linux-devicetree, linux-mmc, linux-samsung-soc, lkml
Hi Javier, You are in a lead of 3 hrs from me.. Surprisingly I send very much same patch just few Mins ago :-) May be we can merge goods in both :-) On 28/01/15 10:10, Javier Martinez Canillas wrote:
quoted hunk ↗ jump to hunk
Many WLAN attached to a SDIO/MMC interface, needs more than one pin for their reset sequence. For example, is very common for chips to have two pins: one for reset and one for power enable. This patch adds support for more reset pins to the pwrseq_simple driver and instead hardcoding a fixed number, it uses the of_gpio_named_count() since the MMC power sequence is only built when CONFIG_OF is enabled. Signed-off-by: Javier Martinez Canillas <redacted> --- drivers/mmc/core/pwrseq_simple.c | 54 ++++++++++++++++++++++++++++++---------- 1 file changed, 41 insertions(+), 13 deletions(-)diff --git a/drivers/mmc/core/pwrseq_simple.c b/drivers/mmc/core/pwrseq_simple.c index 0958c696137f..9e51fe1051c5 100644 --- a/drivers/mmc/core/pwrseq_simple.c +++ b/drivers/mmc/core/pwrseq_simple.c@@ -11,6 +11,7 @@ #include <linux/slab.h> #include <linux/device.h> #include <linux/err.h> +#include <linux/of_gpio.h> #include <linux/gpio/consumer.h> #include <linux/mmc/host.h>@@ -19,34 +20,44 @@ struct mmc_pwrseq_simple { struct mmc_pwrseq pwrseq; - struct gpio_desc *reset_gpio; + struct gpio_desc **reset_gpio;
May be renaming it to reset_gpios makes more sense.. If you make this struct gpio_desc *reset_gpios[0]; You can aviod an extra kmalloc and free ..
+ int nr_gpios;
};
static void mmc_pwrseq_simple_pre_power_on(struct mmc_host *host)
{[...
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq, struct mmc_pwrseq_simple, pwrseq); + int i; - if (!IS_ERR(pwrseq->reset_gpio)) - gpiod_set_value_cansleep(pwrseq->reset_gpio, 1); + for (i = 0; i < pwrseq->nr_gpios; i++) + if (!IS_ERR(pwrseq->reset_gpio[i])) + gpiod_set_value_cansleep(pwrseq->reset_gpio[i], 1);
...]
}
static void mmc_pwrseq_simple_post_power_on(struct mmc_host *host)
{[...
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq, struct mmc_pwrseq_simple, pwrseq); + int i; - if (!IS_ERR(pwrseq->reset_gpio)) - gpiod_set_value_cansleep(pwrseq->reset_gpio, 0); + for (i = 0; i < pwrseq->nr_gpios; i++) + if (!IS_ERR(pwrseq->reset_gpio[i])) + gpiod_set_value_cansleep(pwrseq->reset_gpio[i], 0);
...]
Now that we have more code in mmc_pwrseq_simple_post_power_on() and
mmc_pwrseq_simple_pre_power_on(), Just move most of them into a common
function like:
static void __mmc_pwrseq_simple_power_on_off(struct mmc_host *host,
bool on)
{
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
struct mmc_pwrseq_simple, pwrseq);
int i;
if (!IS_ERR(pwrseq->reset_gpios)) {
for (i = 0; i < pwrseq->ngpios; i++)
gpiod_set_value_cansleep(pwrseq->reset_gpios[i],
on ? : 0);
}
}
static void mmc_pwrseq_simple_pre_power_on(struct mmc_host *host)
{
__mmc_pwrseq_simple_power_on_off(host, true);
}
static void mmc_pwrseq_simple_post_power_on(struct mmc_host *host)
{
__mmc_pwrseq_simple_power_on_off(host, false);
}
quoted hunk ↗ jump to hunk
} static void mmc_pwrseq_simple_free(struct mmc_host *host) { struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq, struct mmc_pwrseq_simple, pwrseq); + int i; - if (!IS_ERR(pwrseq->reset_gpio)) - gpiod_put(pwrseq->reset_gpio); + if (pwrseq->nr_gpios > 0) { + for (i = 0; i < pwrseq->nr_gpios; i++) + if (!IS_ERR(pwrseq->reset_gpio[i])) + gpiod_put(pwrseq->reset_gpio[i]); + kfree(pwrseq->reset_gpio); + } kfree(pwrseq); host->pwrseq = NULL;@@ -63,17 +74,27 @@ int mmc_pwrseq_simple_alloc(struct mmc_host *host, struct device *dev) { struct mmc_pwrseq_simple *pwrseq; int ret = 0; + int i; pwrseq = kzalloc(sizeof(struct mmc_pwrseq_simple), GFP_KERNEL); if (!pwrseq) return -ENOMEM; - pwrseq->reset_gpio = gpiod_get_index(dev, "reset", 0, GPIOD_OUT_HIGH); - if (IS_ERR(pwrseq->reset_gpio) && - PTR_ERR(pwrseq->reset_gpio) != -ENOENT && - PTR_ERR(pwrseq->reset_gpio) != -ENOSYS) { - ret = PTR_ERR(pwrseq->reset_gpio); - goto free; + pwrseq->nr_gpios = of_gpio_named_count(dev->of_node, "reset-gpios"); + if (pwrseq->nr_gpios > 0) {
What happens if there are no gpios? This fuction should return -ENOENT and should not even try to allocate pwrseq? Probably you should do of_gpio_named_count before allocating memory.
+ pwrseq->reset_gpio = kzalloc(sizeof(struct gpio_desc *) *
+ pwrseq->nr_gpios, GFP_KERNEL);
+
+ for (i = 0; i < pwrseq->nr_gpios; i++) {
+ pwrseq->reset_gpio[i] = gpiod_get_index(dev, "reset", i,
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(pwrseq->reset_gpio[i]) &&
+ PTR_ERR(pwrseq->reset_gpio[i]) != -ENOENT &&
+ PTR_ERR(pwrseq->reset_gpio[i]) != -ENOSYS) {
+ ret = PTR_ERR(pwrseq->reset_gpio[i]);is simple to add: while(--i) gpiod_put(pwrseq->reset_gpio[i])
+ goto free; + } + }
quoted hunk ↗ jump to hunk
} pwrseq->pwrseq.ops = &mmc_pwrseq_simple_ops;@@ -81,6 +102,13 @@ int mmc_pwrseq_simple_alloc(struct mmc_host *host, struct device *dev) return 0; free: + if (pwrseq->nr_gpios > 0) { + for (i = 0; i < pwrseq->nr_gpios; i++) + if (!IS_ERR_OR_NULL(pwrseq->reset_gpio[i])) + gpiod_put(pwrseq->reset_gpio[i]); + kfree(pwrseq->reset_gpio); + } + kfree(pwrseq); return ret; }
I get a feeling that am just dumping my patch here.. If possible could you have look at it too. Thanks, srini