mmc: renesas_sdhi: handle 4tap hs400 mode quirk based on SoC revision

Latest datasheet makes it clear that not all ES revisions of the H3 and
M3-W have the 4-tap HS400 mode quirk, currently the quirk is set
unconditionally for these two SoCs. Prepare to handle the quirk based on
SoC revision instead of compatibility value by using soc_device_match()
and set the TMIO_MMC_HAVE_4TAP_HS400 flag explicitly.

The reason for adding a new quirks struct instead of just a flag is that
looking ahead it seems more quirks needs to be handled in a SoC revision
basis.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
index 26da095..6abcf7a 100644 (file)
--- a/drivers/mmc/host/renesas_sdhi_core.c
+++ b/drivers/mmc/host/renesas_sdhi_core.c
@@ -32,6 +32,7 @@
 #include <linux/pinctrl/consumer.h>
 #include <linux/pinctrl/pinctrl-state.h>
 #include <linux/regulator/consumer.h>
+#include <linux/sys_soc.h>
 
 #include "renesas_sdhi.h"
 #include "tmio_mmc.h"
@@ -45,6 +46,10 @@
 #define SDHI_VER_GEN3_SD       0xcc10
 #define SDHI_VER_GEN3_SDMMC    0xcd10
 
+struct renesas_sdhi_quirks {
+       bool hs400_4taps;
+};
+
 static void renesas_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
 {
        u32 val;
@@ -597,11 +602,25 @@ static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
        renesas_sdhi_sdbuf_width(host, enable ? width : 16);
 }
 
+static const struct renesas_sdhi_quirks sdhi_quirks_4tap = {
+       .hs400_4taps = true,
+};
+
+static const struct soc_device_attribute sdhi_quirks_match[]  = {
+       { .soc_id = "r8a7795", .revision = "ES1.*", .data = &sdhi_quirks_4tap },
+       { .soc_id = "r8a7795", .revision = "ES2.0", .data = &sdhi_quirks_4tap },
+       { .soc_id = "r8a7796", .revision = "ES1.0", .data = &sdhi_quirks_4tap },
+       { .soc_id = "r8a7796", .revision = "ES1.1", .data = &sdhi_quirks_4tap },
+       { /* Sentinel. */ },
+};
+
 int renesas_sdhi_probe(struct platform_device *pdev,
                       const struct tmio_mmc_dma_ops *dma_ops)
 {
        struct tmio_mmc_data *mmd = pdev->dev.platform_data;
+       const struct renesas_sdhi_quirks *quirks = NULL;
        const struct renesas_sdhi_of_data *of_data;
+       const struct soc_device_attribute *attr;
        struct tmio_mmc_data *mmc_data;
        struct tmio_mmc_dma *dma_priv;
        struct tmio_mmc_host *host;
@@ -611,6 +630,10 @@ int renesas_sdhi_probe(struct platform_device *pdev,
 
        of_data = of_device_get_match_data(&pdev->dev);
 
+       attr = soc_device_match(sdhi_quirks_match);
+       if (attr)
+               quirks = attr->data;
+
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res)
                return -EINVAL;
@@ -676,6 +699,9 @@ int renesas_sdhi_probe(struct platform_device *pdev,
        host->multi_io_quirk    = renesas_sdhi_multi_io_quirk;
        host->dma_ops           = dma_ops;
 
+       if (quirks && quirks->hs400_4taps)
+               mmc_data->flags |= TMIO_MMC_HAVE_4TAP_HS400;
+
        /* For some SoC, we disable internal WP. GPIO may override this */
        if (mmc_can_gpio_ro(host->mmc))
                mmc_data->capabilities2 &= ~MMC_CAP2_NO_WRITE_PROTECT;