Re: [PATCH 13/41] mmc: host: omap_hsmmc: Add support to set IODELAY values

From: Rob Herring
Date: Tue May 23 2017 - 10:55:50 EST


On Fri, May 19, 2017 at 01:45:13PM +0530, Kishon Vijay Abraham I wrote:
> The data manual of J6/J6 Eco recommends to set different IODELAY values
> depending on the mode in which the MMC/SD is enumerated in order to
> ensure IO timings are met.
>
> Add support to set the IODELAY values depending on the various MMC
> modes using the pinctrl APIs.
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> [nsekhar@xxxxxx: introduce OMAP_HSMMC_SETUP_PINCTRL()]
> Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>
> ---
> .../devicetree/bindings/mmc/ti-omap-hsmmc.txt | 5 +
> drivers/mmc/host/omap_hsmmc.c | 124 ++++++++++++++++++++-
> include/linux/platform_data/hsmmc-omap.h | 3 +
> 3 files changed, 129 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> index 258e25af10f7..dcf0b777c031 100644
> --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> @@ -20,6 +20,11 @@ Optional properties:
> ti,dual-volt: boolean, supports dual voltage cards
> <supply-name>-supply: phandle to the regulator device tree node
> "supply-name" examples are "vmmc", "vmmc_aux" etc
> +pinctrl-names: Should be a list of pinctrl state names and can be "sdr104",
> +"hs200_1_8v", "ddr50", "sdr50", "sdr25", "sdr12", "hs", "ddr_1_8v" or
> +"default".
> +pinctrl-<num>: Phandle referencing pin configuration of the sd/emmc controller.
> +See: Documentation/devicetree/bindings/pinctrl/pinctrl-binding.txt
> ti,non-removable: non-removable slot (like eMMC)
> ti,needs-special-reset: Requires a special softreset sequence
> ti,needs-special-hs-handling: HSMMC IP needs special setting for handling High Speed

Binding looks fine, but...

> @@ -2388,6 +2427,73 @@ static inline struct omap_hsmmc_platform_data
> }
> #endif
>
> +#define OMAP_HSMMC_SETUP_PINCTRL(capvar, capmask, mode) \
> + do { \

This is kind of ugly. Why not make it a function. Just return
pinctrl_state ptr.

> + struct pinctrl_state *s = ERR_PTR(-ENODEV); \
> + char str[20]; \
> + char *version = host->pdata->version; \
> + \
> + if (!(mmc->capvar & (capmask))) \
> + break; \
> + \
> + if (host->pdata->version) { \
> + sprintf(str, "%s-%s", #mode, version); \
> + s = pinctrl_lookup_state(host->pinctrl, str); \
> + } \
> + \
> + if (IS_ERR(s)) { \
> + sprintf(str, "%s", #mode); \
> + s = pinctrl_lookup_state(host->pinctrl, str); \
> + } \
> + \
> + if (IS_ERR(s)) { \
> + dev_err(host->dev, "no pinctrl state for %s " \
> + "mode\n", #mode); \
> + mmc->capvar &= ~(capmask); \
> + } else { \
> + host->mode##_pinctrl_state = s; \
> + } \
> + \
> + } while (0)
> +
> +static int omap_hsmmc_get_iodelay_pinctrl_state(struct omap_hsmmc_host *host)
> +{
> + struct mmc_host *mmc = host->mmc;
> +
> + if (!(host->pdata->controller_flags & OMAP_HSMMC_REQUIRE_IODELAY))
> + return 0;
> +
> + host->pinctrl = devm_pinctrl_get(host->dev);
> + if (IS_ERR(host->pinctrl)) {
> + dev_err(host->dev, "Cannot get pinctrl\n");
> + return PTR_ERR(host->pinctrl);
> + }
> +
> + host->default_pinctrl_state = pinctrl_lookup_state(host->pinctrl,
> + "default");
> + if (IS_ERR(host->default_pinctrl_state)) {
> + dev_err(host->dev,
> + "no pinctrl state for default mode\n");
> + return PTR_ERR(host->default_pinctrl_state);
> + }
> +
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_UHS_SDR104, sdr104);
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_UHS_DDR50, ddr50);
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_UHS_SDR50, sdr50);
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_UHS_SDR25, sdr25);
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_UHS_SDR12, sdr12);
> + OMAP_HSMMC_SETUP_PINCTRL(caps, MMC_CAP_1_8V_DDR, ddr_1_8v);
> + OMAP_HSMMC_SETUP_PINCTRL(caps,
> + MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED,
> + hs);
> + OMAP_HSMMC_SETUP_PINCTRL(caps2, MMC_CAP2_HS200_1_8V_SDR,
> + hs200_1_8v);
> +
> + host->pinctrl_state = host->default_pinctrl_state;
> +
> + return 0;
> +}
> +
> static int omap_hsmmc_probe(struct platform_device *pdev)
> {
> struct omap_hsmmc_platform_data *pdata = pdev->dev.platform_data;