mmc: slot-gpio: Add debouncing capability to mmc_gpio_request_cd()

Add a debounce parameter to the mmc_gpio_request_cd() function that
enables GPIO debouncing when set to a non-zero value. This can be used
by MMC host drivers to enable debouncing on the card detect signal.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Laurent Pinchart 2013-08-08 12:38:31 +02:00 committed by Chris Ball
parent 7725a52c03
commit 214fc309d1
10 changed files with 25 additions and 10 deletions

View file

@ -374,7 +374,7 @@ int mmc_of_parse(struct mmc_host *host)
if (!(flags & OF_GPIO_ACTIVE_LOW))
gpio_inv_cd = true;
ret = mmc_gpio_request_cd(host, gpio);
ret = mmc_gpio_request_cd(host, gpio, 0);
if (ret < 0) {
dev_err(host->parent,
"Failed to request CD GPIO #%d: %d!\n",

View file

@ -135,6 +135,7 @@ EXPORT_SYMBOL(mmc_gpio_request_ro);
* mmc_gpio_request_cd - request a gpio for card-detection
* @host: mmc host
* @gpio: gpio number requested
* @debounce: debounce time in microseconds
*
* As devm_* managed functions are used in mmc_gpio_request_cd(), client
* drivers do not need to explicitly call mmc_gpio_free_cd() for freeing up,
@ -143,9 +144,14 @@ EXPORT_SYMBOL(mmc_gpio_request_ro);
* switching for card-detection, they are responsible for calling
* mmc_gpio_request_cd() and mmc_gpio_free_cd() as a pair on their own.
*
* If GPIO debouncing is desired, set the debounce parameter to a non-zero
* value. The caller is responsible for ensuring that the GPIO driver associated
* with the GPIO supports debouncing, otherwise an error will be returned.
*
* Returns zero on success, else an error.
*/
int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio,
unsigned int debounce)
{
struct mmc_gpio *ctx;
int irq = gpio_to_irq(gpio);
@ -167,6 +173,12 @@ int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
*/
return ret;
if (debounce) {
ret = gpio_set_debounce(gpio, debounce);
if (ret < 0)
return ret;
}
/*
* Even if gpio_to_irq() returns a valid IRQ number, the platform might
* still prefer to poll, e.g., because that IRQ number is already used

View file

@ -713,7 +713,7 @@ static int jz4740_mmc_request_gpios(struct mmc_host *mmc,
mmc->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
if (gpio_is_valid(pdata->gpio_card_detect)) {
ret = mmc_gpio_request_cd(mmc, pdata->gpio_card_detect);
ret = mmc_gpio_request_cd(mmc, pdata->gpio_card_detect, 0);
if (ret)
return ret;
}

View file

@ -757,7 +757,8 @@ static int __init mvsd_probe(struct platform_device *pdev)
if (mvsd_data->gpio_card_detect &&
gpio_is_valid(mvsd_data->gpio_card_detect)) {
ret = mmc_gpio_request_cd(mmc,
mvsd_data->gpio_card_detect);
mvsd_data->gpio_card_detect,
0);
if (ret)
goto out;
} else {

View file

@ -616,7 +616,7 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev)
/* card_detect */
switch (boarddata->cd_type) {
case ESDHC_CD_GPIO:
err = mmc_gpio_request_cd(host->mmc, boarddata->cd_gpio);
err = mmc_gpio_request_cd(host->mmc, boarddata->cd_gpio, 0);
if (err) {
dev_err(mmc_dev(host->mmc),
"failed to request card-detect gpio!\n");

View file

@ -278,7 +278,8 @@ static int sdhci_pxav3_probe(struct platform_device *pdev)
host->mmc->pm_caps |= pdata->pm_caps;
if (gpio_is_valid(pdata->ext_cd_gpio)) {
ret = mmc_gpio_request_cd(host->mmc, pdata->ext_cd_gpio);
ret = mmc_gpio_request_cd(host->mmc, pdata->ext_cd_gpio,
0);
if (ret) {
dev_err(mmc_dev(host->mmc),
"failed to allocate card detect gpio\n");

View file

@ -84,7 +84,7 @@ static int sdhci_sirf_probe(struct platform_device *pdev)
* gets setup in sdhci_add_host() and we oops.
*/
if (gpio_is_valid(priv->gpio_cd)) {
ret = mmc_gpio_request_cd(host->mmc, priv->gpio_cd);
ret = mmc_gpio_request_cd(host->mmc, priv->gpio_cd, 0);
if (ret) {
dev_err(&pdev->dev, "card detect irq request failed: %d\n",
ret);

View file

@ -1436,7 +1436,7 @@ static int sh_mmcif_probe(struct platform_device *pdev)
}
if (pd && pd->use_cd_gpio) {
ret = mmc_gpio_request_cd(mmc, pd->cd_gpio);
ret = mmc_gpio_request_cd(mmc, pd->cd_gpio, 0);
if (ret < 0)
goto erqcd;
}

View file

@ -1110,7 +1110,7 @@ int tmio_mmc_host_probe(struct tmio_mmc_host **host,
dev_pm_qos_expose_latency_limit(&pdev->dev, 100);
if (pdata->flags & TMIO_MMC_USE_GPIO_CD) {
ret = mmc_gpio_request_cd(mmc, pdata->cd_gpio);
ret = mmc_gpio_request_cd(mmc, pdata->cd_gpio, 0);
if (ret < 0) {
tmio_mmc_host_remove(_host);
return ret;

View file

@ -18,7 +18,8 @@ int mmc_gpio_request_ro(struct mmc_host *host, unsigned int gpio);
void mmc_gpio_free_ro(struct mmc_host *host);
int mmc_gpio_get_cd(struct mmc_host *host);
int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio);
int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio,
unsigned int debounce);
void mmc_gpio_free_cd(struct mmc_host *host);
#endif