mmc: sdhci-esdhc-imx: extend card_detect and write_protect support for mx5

The patch extends card_detect and write_protect support to get mx5
family and more scenarios supported.  The changes include:

 * Turn platform_data from optional to mandatory
 * Add cd_types and wp_types into platform_data to cover more use
   cases
 * Remove the use of flag ESDHC_FLAG_GPIO_FOR_CD
 * Adjust some machine codes to adopt the platform_data changes
 * Work around the issue that software reset will get card detection
   circuit stop working

With this patch, card_detect and write_protect gets supported on
mx5 based platforms.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Chris Ball <cjb@laptop.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Acked-by: Chris Ball <cjb@laptop.org>

1 files changed, 87 insertions, 51 deletions

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 710b706f4fcf..4269bb498ff0 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -29,7 +29,6 @@
 #define SDHCI_VENDOR_SPEC               0xC0
 #define  SDHCI_VENDOR_SPEC_SDIO_QUIRK   0x00000002
 
-#define ESDHC_FLAG_GPIO_FOR_CD          (1 << 0)
 /*
  * The CMDTYPE of the CMD register (offset 0xE) should be set to
  * "11" when the STOP CMD12 is issued on imx53 to abort one
@@ -58,19 +57,15 @@ static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, i
 
 static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
 {
-        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
-        struct pltfm_imx_data *imx_data = pltfm_host->priv;
+        struct esdhc_platform_data *boarddata =
+                        host->mmc->parent->platform_data;
 
-        /* fake CARD_PRESENT flag on mx25/35 */
+        /* fake CARD_PRESENT flag */
         u32 val = readl(host->ioaddr + reg);
 
         if (unlikely((reg == SDHCI_PRESENT_STATE)
-                        && (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD))) {
-                struct esdhc_platform_data *boarddata =
-                                host->mmc->parent->platform_data;
-
-                if (boarddata && gpio_is_valid(boarddata->cd_gpio)
-                                && gpio_get_value(boarddata->cd_gpio))
+                        && gpio_is_valid(boarddata->cd_gpio))) {
+                if (gpio_get_value(boarddata->cd_gpio))
                         /* no card, if a valid gpio says so... */
                         val &= ~SDHCI_CARD_PRESENT;
                 else
@@ -85,12 +80,13 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
 {
         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
         struct pltfm_imx_data *imx_data = pltfm_host->priv;
+        struct esdhc_platform_data *boarddata =
+                        host->mmc->parent->platform_data;
 
         if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)
-                        && (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)))
+                        && (boarddata->cd_type == ESDHC_CD_GPIO)))
                 /*
                  * these interrupts won't work with a custom card_detect gpio
-                 * (only applied to mx25/35)
                  */
                 val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT);
 
@@ -173,6 +169,17 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
                 return;
         }
         esdhc_clrset_le(host, 0xff, val, reg);
+
+        /*
+         * The esdhc has a design violation to SDHC spec which tells
+         * that software reset should not affect card detection circuit.
+         * But esdhc clears its SYSCTL register bits [0..2] during the
+         * software reset.  This will stop those clocks that card detection
+         * circuit relies on.  To work around it, we turn the clocks on back
+         * to keep card detection circuit functional.
+         */
+        if ((reg == SDHCI_SOFTWARE_RESET) && (val & 1))
+                esdhc_clrset_le(host, 0x7, 0x7, ESDHC_SYSTEM_CONTROL);
 }
 
 static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
@@ -189,6 +196,25 @@ static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
         return clk_get_rate(pltfm_host->clk) / 256 / 16;
 }
 
+static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
+{
+        struct esdhc_platform_data *boarddata =
+                        host->mmc->parent->platform_data;
+
+        switch (boarddata->wp_type) {
+        case ESDHC_WP_GPIO:
+                if (gpio_is_valid(boarddata->wp_gpio))
+                        return gpio_get_value(boarddata->wp_gpio);
+        case ESDHC_WP_CONTROLLER:
+                return !(readl(host->ioaddr + SDHCI_PRESENT_STATE) &
+                               SDHCI_WRITE_PROTECT);
+        case ESDHC_WP_NONE:
+                break;
+        }
+
+        return -ENOSYS;
+}
+
 static struct sdhci_ops sdhci_esdhc_ops = {
         .read_l = esdhc_readl_le,
         .read_w = esdhc_readw_le,
@@ -198,6 +224,7 @@ static struct sdhci_ops sdhci_esdhc_ops = {
         .set_clock = esdhc_set_clock,
         .get_max_clock = esdhc_pltfm_get_max_clock,
         .get_min_clock = esdhc_pltfm_get_min_clock,
+        .get_ro = esdhc_pltfm_get_ro,
 };
 
 static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
@@ -207,17 +234,6 @@ static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
         .ops = &sdhci_esdhc_ops,
 };
 
-static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
-{
-        struct esdhc_platform_data *boarddata =
-                        host->mmc->parent->platform_data;
-
-        if (boarddata && gpio_is_valid(boarddata->wp_gpio))
-                return gpio_get_value(boarddata->wp_gpio);
-        else
-                return -ENOSYS;
-}
-
 static irqreturn_t cd_irq(int irq, void *data)
 {
         struct sdhci_host *sdhost = (struct sdhci_host *)data;
@@ -258,47 +274,65 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
         if (!cpu_is_mx25())
                 host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
 
-        if (cpu_is_mx25() || cpu_is_mx35()) {
+        if (cpu_is_mx25() || cpu_is_mx35())
                 /* Fix errata ENGcm07207 present on i.MX25 and i.MX35 */
                 host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK;
-                /* write_protect can't be routed to controller, use gpio */
-                sdhci_esdhc_ops.get_ro = esdhc_pltfm_get_ro;
-        }
 
         if (!(cpu_is_mx25() || cpu_is_mx35() || cpu_is_mx51()))
                 imx_data->flags |= ESDHC_FLAG_MULTIBLK_NO_INT;
 
         boarddata = host->mmc->parent->platform_data;
-        if (boarddata) {
+        if (!boarddata) {
+                dev_err(mmc_dev(host->mmc), "no board data!\n");
+                err = -EINVAL;
+                goto no_board_data;
+        }
+
+        /* write_protect */
+        if (boarddata->wp_type == ESDHC_WP_GPIO) {
                 err = gpio_request_one(boarddata->wp_gpio, GPIOF_IN, "ESDHC_WP");
                 if (err) {
                         dev_warn(mmc_dev(host->mmc),
-                                "no write-protect pin available!\n");
-                        boarddata->wp_gpio = err;
+                                 "no write-protect pin available!\n");
+                        boarddata->wp_gpio = -EINVAL;
                 }
+        } else {
+                boarddata->wp_gpio = -EINVAL;
+        }
+
+        /* card_detect */
+        if (boarddata->cd_type != ESDHC_CD_GPIO)
+                boarddata->cd_gpio = -EINVAL;
 
+        switch (boarddata->cd_type) {
+        case ESDHC_CD_GPIO:
                 err = gpio_request_one(boarddata->cd_gpio, GPIOF_IN, "ESDHC_CD");
                 if (err) {
-                        dev_warn(mmc_dev(host->mmc),
+                        dev_err(mmc_dev(host->mmc),
                                 "no card-detect pin available!\n");
                         goto no_card_detect_pin;
                 }
 
-                /* i.MX5x has issues to be researched */
-                if (!cpu_is_mx25() && !cpu_is_mx35())
-                        goto not_supported;
-
                 err = request_irq(gpio_to_irq(boarddata->cd_gpio), cd_irq,
                                  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
                                  mmc_hostname(host->mmc), host);
                 if (err) {
-                        dev_warn(mmc_dev(host->mmc), "request irq error\n");
+                        dev_err(mmc_dev(host->mmc), "request irq error\n");
                         goto no_card_detect_irq;
                 }
+                /* fall through */
 
-                imx_data->flags |= ESDHC_FLAG_GPIO_FOR_CD;
-                /* Now we have a working card_detect again */
+        case ESDHC_CD_CONTROLLER:
+                /* we have a working card_detect back */
                 host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
+                break;
+
+        case ESDHC_CD_PERMANENT:
+                host->mmc->caps = MMC_CAP_NONREMOVABLE;
+                break;
+
+        case ESDHC_CD_NONE:
+                break;
         }
 
         err = sdhci_add_host(host);
@@ -307,16 +341,20 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
 
         return 0;
 
- no_card_detect_irq:
-        gpio_free(boarddata->cd_gpio);
- no_card_detect_pin:
-        boarddata->cd_gpio = err;
- not_supported:
-        kfree(imx_data);
- err_add_host:
+err_add_host:
+        if (gpio_is_valid(boarddata->cd_gpio))
+                free_irq(gpio_to_irq(boarddata->cd_gpio), host);
+no_card_detect_irq:
+        if (gpio_is_valid(boarddata->cd_gpio))
+                gpio_free(boarddata->cd_gpio);
+        if (gpio_is_valid(boarddata->wp_gpio))
+                gpio_free(boarddata->wp_gpio);
+no_card_detect_pin:
+no_board_data:
         clk_disable(pltfm_host->clk);
         clk_put(pltfm_host->clk);
- err_clk_get:
+err_clk_get:
+        kfree(imx_data);
         sdhci_pltfm_free(pdev);
         return err;
 }
@@ -331,14 +369,12 @@ static int __devexit sdhci_esdhc_imx_remove(struct platform_device *pdev)
 
         sdhci_remove_host(host, dead);
 
-        if (boarddata && gpio_is_valid(boarddata->wp_gpio))
+        if (gpio_is_valid(boarddata->wp_gpio))
                 gpio_free(boarddata->wp_gpio);
 
-        if (boarddata && gpio_is_valid(boarddata->cd_gpio)) {
+        if (gpio_is_valid(boarddata->cd_gpio)) {
+                free_irq(gpio_to_irq(boarddata->cd_gpio), host);
                 gpio_free(boarddata->cd_gpio);
-
-                if (!(host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION))
-                        free_irq(gpio_to_irq(boarddata->cd_gpio), host);
         }
 
         clk_disable(pltfm_host->clk);