From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: [PATCH V2 16/16] mmc: omap_hsmmc: add a hardware reset before initialization Date: Fri, 6 May 2011 12:14:15 +0300 Message-ID: <1304673255-31634-17-git-send-email-adrian.hunter@nokia.com> References: <1304673255-31634-1-git-send-email-adrian.hunter@nokia.com> Return-path: In-Reply-To: <1304673255-31634-1-git-send-email-adrian.hunter@nokia.com> Sender: linux-mmc-owner@vger.kernel.org To: Tony Lindgren Cc: Madhusudhan Chikkature , linux-omap Mailing List , linux-mmc Mailing List , linux-arm Mailing List , Adrian Hunter List-Id: linux-omap@vger.kernel.org After a warm restart, an eMMC which cannot be powered off is in an unknown state, so reset it to be sure it will initialize. Signed-off-by: Adrian Hunter --- drivers/mmc/host/omap_hsmmc.c | 38 +++++++++++++++++++++++++++++++++++++- 1 files changed, 37 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index e1c9017..70b8ef8 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -530,10 +530,25 @@ static int omap_hsmmc_gpio_init(struct omap_mmc_platform_data *pdata) } else pdata->slots[0].gpio_wp = -EINVAL; + if (gpio_is_valid(pdata->slots[0].gpio_hw_reset)) { + ret = gpio_request(pdata->slots[0].gpio_hw_reset, + "mmc_hw_reset"); + if (ret) + goto err_free_wp; + ret = gpio_direction_output(pdata->slots[0].gpio_hw_reset, 1); + if (ret) + goto err_free_hw_reset; + } else + pdata->slots[0].gpio_hw_reset = -EINVAL; + return 0; + +err_free_hw_reset: + gpio_free(pdata->slots[0].gpio_hw_reset); err_free_wp: - gpio_free(pdata->slots[0].gpio_wp); + if (gpio_is_valid(pdata->slots[0].gpio_wp)) + gpio_free(pdata->slots[0].gpio_wp); err_free_cd: if (gpio_is_valid(pdata->slots[0].switch_pin)) err_free_sp: @@ -543,6 +558,8 @@ err_free_sp: static void omap_hsmmc_gpio_free(struct omap_mmc_platform_data *pdata) { + if (gpio_is_valid(pdata->slots[0].gpio_hw_reset)) + gpio_free(pdata->slots[0].gpio_hw_reset); if (gpio_is_valid(pdata->slots[0].gpio_wp)) gpio_free(pdata->slots[0].gpio_wp); if (gpio_is_valid(pdata->slots[0].switch_pin)) @@ -803,6 +820,18 @@ static void omap_hsmmc_context_save(struct omap_hsmmc_host *host) #endif +static void omap_hsmmc_do_hw_reset(struct omap_hsmmc_host *host) +{ + if (!gpio_is_valid(mmc_slot(host).gpio_hw_reset)) + return; + + gpio_set_value_cansleep(mmc_slot(host).gpio_hw_reset, 0); + udelay(9); + gpio_set_value_cansleep(mmc_slot(host).gpio_hw_reset, 1); + usleep_range(1000, 2000); + printk(KERN_INFO "%s: hardware reset done\n", mmc_hostname(host->mmc)); +} + /* * Send init stream sequence to card * before sending IDLE command @@ -815,6 +844,13 @@ static void send_init_stream(struct omap_hsmmc_host *host) if (host->protect_card) return; + /* + * After a warm restart, an eMMC which cannot be powered off is in an + * unknown state so reset it to be sure it will initialize. + */ + if (mmc_slot(host).no_off) + omap_hsmmc_do_hw_reset(host); + disable_irq(host->irq); OMAP_HSMMC_WRITE(host->base, IE, INT_EN_MASK); -- 1.7.0.4