On Sat, 2019-05-04 at 20:24 +1000, NeilBrown wrote:
> The mtk-sd silicon has integrated card-detect logic that is
> enabled on the MT7621. The circuit is phased out on newer hardware so
> we should be careful to only enabled it on hardware known to support
> it. This a new "use_internal_cd" flag in struct mtk_mmc_compatible.
>
> If the sdhci isn't marked non-removable and doesn't have a
> cd-gpio configured, and if use_internal_cd is set, then assume the
> internal cd logic should be used as recommended by
> Documentation/devicetree/bindings/mmc/mmc.txt
>
> Signed-off-by: NeilBrown <neil@xxxxxxxxxx>
Reviewed-by:Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
> ---
> drivers/mmc/host/mtk-sd.c | 64 ++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 60 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 0c2be4f54b1f..c518cc208a1f 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -300,6 +300,8 @@
> #define CMD_TIMEOUT (HZ/10 * 5) /* 100ms x5 */
> #define DAT_TIMEOUT (HZ * 5) /* 1000ms x5 */
>
> +#define DEFAULT_DEBOUNCE (8) /* 8 cycles CD debounce */
> +
> #define PAD_DELAY_MAX 32 /* PAD delay cells */
> /*--------------------------------------------------------------------------*/
> /* Descriptor Structure */
> @@ -372,6 +374,7 @@ struct mtk_mmc_compatible {
> bool stop_clk_fix;
> bool enhance_rx;
> bool support_64g;
> + bool use_internal_cd;
> };
>
> struct msdc_tune_para {
> @@ -430,6 +433,7 @@ struct msdc_host {
> bool hs400_cmd_resp_sel_rising;
> /* cmd response sample selection for HS400 */
> bool hs400_mode; /* current eMMC will run at hs400 mode */
> + bool internal_cd; /* Use internal card-detect logic */
> struct msdc_save_para save_para; /* used when gate HCLK */
> struct msdc_tune_para def_tune_para; /* default tune setting */
> struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */
> @@ -526,6 +530,7 @@ static const struct mtk_mmc_compatible mt7620_compat = {
> .busy_check = false,
> .stop_clk_fix = false,
> .enhance_rx = false,
> + .use_internal_cd = true,
> };
>
> static const struct of_device_id msdc_of_ids[] = {
> @@ -1430,6 +1435,12 @@ static irqreturn_t msdc_irq(int irq, void *dev_id)
> sdio_signal_irq(host->mmc);
> }
>
> + if ((events & event_mask) & MSDC_INT_CDSC) {
> + if (host->internal_cd)
> + mmc_detect_change(host->mmc, msecs_to_jiffies(20));
> + events &= ~MSDC_INT_CDSC;
> + }
> +
> if (!(events & (event_mask & ~MSDC_INT_SDIOIRQ)))
> break;
>
> @@ -1463,14 +1474,24 @@ static void msdc_init_hw(struct msdc_host *host)
> /* Reset */
> msdc_reset_hw(host);
>
> - /* Disable card detection */
> - sdr_clr_bits(host->base + MSDC_PS, MSDC_PS_CDEN);
> -
> /* Disable and clear all interrupts */
> writel(0, host->base + MSDC_INTEN);
> val = readl(host->base + MSDC_INT);
> writel(val, host->base + MSDC_INT);
>
> + /* Configure card detection */
> + if (host->internal_cd) {
> + sdr_set_field(host->base + MSDC_PS, MSDC_PS_CDDEBOUNCE,
> + DEFAULT_DEBOUNCE);
> + sdr_set_bits(host->base + MSDC_PS, MSDC_PS_CDEN);
> + sdr_set_bits(host->base + MSDC_INTEN, MSDC_INTEN_CDSC);
> + sdr_set_bits(host->base + SDC_CFG, SDC_CFG_INSWKUP);
> + } else {
> + sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_INSWKUP);
> + sdr_clr_bits(host->base + MSDC_PS, MSDC_PS_CDEN);
> + sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INTEN_CDSC);
> + }
> +
> if (host->top_base) {
> writel(0, host->top_base + EMMC_TOP_CONTROL);
> writel(0, host->top_base + EMMC_TOP_CMD);
> @@ -1580,6 +1601,13 @@ static void msdc_init_hw(struct msdc_host *host)
> static void msdc_deinit_hw(struct msdc_host *host)
> {
> u32 val;
> +
> + if (host->internal_cd) {
> + /* Disabled card-detect */
> + sdr_clr_bits(host->base + MSDC_PS, MSDC_PS_CDEN);
> + sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_INSWKUP);
> + }
> +
> /* Disable and clear all interrupts */
> writel(0, host->base + MSDC_INTEN);
>
> @@ -2078,13 +2106,31 @@ static void msdc_ack_sdio_irq(struct mmc_host *mmc)
> __msdc_enable_sdio_irq(mmc, 1);
> }
>
> +static int msdc_get_cd(struct mmc_host *mmc)
> +{
> + struct msdc_host *host = mmc_priv(mmc);
> + int val;
> +
> + if (mmc->caps & MMC_CAP_NONREMOVABLE)
> + return 1;
> +
> + if (!host->internal_cd)
> + return mmc_gpio_get_cd(mmc);
> +
> + val = readl(host->base + MSDC_PS) & MSDC_PS_CDSTS;
> + if (mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH)
> + return !!val;
> + else
> + return !val;
> +}
> +
> static const struct mmc_host_ops mt_msdc_ops = {
> .post_req = msdc_post_req,
> .pre_req = msdc_pre_req,
> .request = msdc_ops_request,
> .set_ios = msdc_ops_set_ios,
> .get_ro = mmc_gpio_get_ro,
> - .get_cd = mmc_gpio_get_cd,
> + .get_cd = msdc_get_cd,
> .enable_sdio_irq = msdc_enable_sdio_irq,
> .ack_sdio_irq = msdc_ack_sdio_irq,
> .start_signal_voltage_switch = msdc_ops_switch_volt,
> @@ -2216,6 +2262,16 @@ static int msdc_drv_probe(struct platform_device *pdev)
> else
> mmc->f_min = DIV_ROUND_UP(host->src_clk_freq, 4 * 4095);
>
> + if (!(mmc->caps & MMC_CAP_NONREMOVABLE) &&
> + !mmc_can_gpio_cd(mmc) &&
> + host->dev_comp->use_internal_cd) {
> + /*
> + * Is removable but no GPIO declared, so
> + * use internal functionality.
> + */
> + host->internal_cd = true;
> + }
> +
> if (mmc->caps & MMC_CAP_SDIO_IRQ)
> mmc->caps2 |= MMC_CAP2_SDIO_IRQ_NOTHREAD;
>
>
>
