Re: [PATCH V2 3/3] mmc: sdhci-msm: Use internal voltage control

From: Evan Green
Date: Fri Sep 21 2018 - 16:10:31 EST

Next message: Nicolin Chen: "[PATCH v2 0/2] Add an initial DT binding doc for ina3221"
Previous message: Evan Green: "Re: [PATCH V2 1/3] mmc: sdhci: Allow platform controlled voltage switching"
In reply to: Veerabhadrarao Badiganti: "[PATCH V2 3/3] mmc: sdhci-msm: Use internal voltage control"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Wed, Sep 19, 2018 at 11:24 PM Veerabhadrarao Badiganti
<vbadigan@xxxxxxxxxxxxxx> wrote:
>
> From: Vijay Viswanath <vviswana@xxxxxxxxxxxxxx>
>
> Some sdhci-msm controllers require that voltage switching be done after
> the HW is ready for it. The HW informs its readiness through power irq.
> The voltage switching should happen only then.
>
> Use the quirk for internal voltage switching and then control the
> voltage switching using power irq.
>
> Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
> Signed-off-by: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>
> Signed-off-by: Vijay Viswanath <vviswana@xxxxxxxxxxxxxx>
> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-msm.c | 211 +++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 203 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 3cc8bfe..486462d 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -43,7 +43,9 @@
> #define CORE_PWRCTL_IO_LOW BIT(2)
> #define CORE_PWRCTL_IO_HIGH BIT(3)
> #define CORE_PWRCTL_BUS_SUCCESS BIT(0)
> +#define CORE_PWRCTL_BUS_FAIL BIT(1)
> #define CORE_PWRCTL_IO_SUCCESS BIT(2)
> +#define CORE_PWRCTL_IO_FAIL BIT(3)
> #define REQ_BUS_OFF BIT(0)
> #define REQ_BUS_ON BIT(1)
> #define REQ_IO_LOW BIT(2)
> @@ -258,6 +260,10 @@ struct sdhci_msm_host {
> bool mci_removed;
> const struct sdhci_msm_variant_ops *var_ops;
> const struct sdhci_msm_offset *offset;
> + bool vmmc_load;
> + u32 vmmc_level[2];
> + bool vqmmc_load;
> + u32 vqmmc_level[2];
> };
>
> static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host)
> @@ -1211,6 +1217,74 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host,
> sdhci_msm_hs400(host, &mmc->ios);
> }
>
> +static int sdhci_msm_set_vmmc(struct sdhci_msm_host *msm_host,
> + struct mmc_host *mmc, int level)
> +{
> + int load = msm_host->vmmc_level[level];
> + int ret;
> +
> + if (IS_ERR(mmc->supply.vmmc))
> + return 0;
> +
> + if (msm_host->vmmc_load) {
> + ret = regulator_set_load(mmc->supply.vmmc, load);
> + if (ret)
> + goto out;
> + }
> +
> + ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd);

This is new, isn't it? Could you explain why this is needed?

> +out:
> + if (ret)
> + pr_err("%s: vmmc set load/ocr failed: %d\n",
> + mmc_hostname(mmc), ret);
> +
> + return ret;
> +}
> +
> +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host,
> + struct mmc_host *mmc, int level)
> +{
> + int load = msm_host->vqmmc_level[level];
> + int ret;
> + struct mmc_ios ios;
> +
> + if (IS_ERR(mmc->supply.vqmmc))
> + return 0;
> +
> + if (msm_host->vqmmc_load) {
> + ret = regulator_set_load(mmc->supply.vqmmc, load);
> + if (ret)
> + goto out;
> + }
> +
> + /*
> + * The IO voltage regulator maynot always support a voltage close to

s/maynot/may not/

> + * vdd. Set IO voltage based on capability of the regulator.

remove extra space between on and capability.

> + */
> + if (level) {
> + if (msm_host->caps_0 & CORE_3_0V_SUPPORT)
> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_330;
> + else if (msm_host->caps_0 & CORE_1_8V_SUPPORT)
> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_180;
> + if (msm_host->caps_0 & CORE_VOLT_SUPPORT) {
> + pr_debug("%s: %s: setting signal voltage: %d\n",
> + mmc_hostname(mmc), __func__,
> + ios.signal_voltage);
> + ret = mmc_regulator_set_vqmmc(mmc, &ios);
> + if (ret)
> + goto out;
> + }
> + ret = regulator_enable(mmc->supply.vqmmc);
> + } else {
> + ret = regulator_disable(mmc->supply.vqmmc);
> + }
> +out:
> + if (ret)
> + pr_err("%s: vqmmc failed: %d\n", mmc_hostname(mmc), ret);
> +
> + return ret;
> +}
> +
> static inline void sdhci_msm_init_pwr_irq_wait(struct sdhci_msm_host *msm_host)
> {
> init_waitqueue_head(&msm_host->pwr_irq_wait);
> @@ -1314,8 +1388,9 @@ static void sdhci_msm_handle_pwr_irq(struct sdhci_host *host, int irq)
> {
> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> + struct mmc_host *mmc = host->mmc;
> u32 irq_status, irq_ack = 0;
> - int retry = 10;
> + int retry = 10, ret = 0;
> u32 pwr_state = 0, io_level = 0;
> u32 config;
> const struct sdhci_msm_offset *msm_offset = msm_host->offset;
> @@ -1351,14 +1426,34 @@ static void sdhci_msm_handle_pwr_irq(struct sdhci_host *host, int irq)
>
> /* Handle BUS ON/OFF*/
> if (irq_status & CORE_PWRCTL_BUS_ON) {
> - pwr_state = REQ_BUS_ON;
> - io_level = REQ_IO_HIGH;
> - irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
> + ret = sdhci_msm_set_vmmc(msm_host, mmc, 1);
> + if (!ret)
> + ret = sdhci_msm_set_vqmmc(msm_host, mmc, 1);

Should you put vmmc back to 0 if setting vqmmc to 1 fails?

> +
> + if (!ret) {
> + pwr_state = REQ_BUS_ON;
> + io_level = REQ_IO_HIGH;
> + irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
> + } else {
> + pr_err("%s: BUS_ON req failed(%d). irq_status: 0x%08x\n",
> + mmc_hostname(mmc), ret, irq_status);
> + irq_ack |= CORE_PWRCTL_BUS_FAIL;
> + }
> }
> if (irq_status & CORE_PWRCTL_BUS_OFF) {
> - pwr_state = REQ_BUS_OFF;
> - io_level = REQ_IO_LOW;
> - irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
> + ret = sdhci_msm_set_vmmc(msm_host, mmc, 0);
> + if (!ret)
> + ret = sdhci_msm_set_vqmmc(msm_host, mmc, 0);
> +
> + if (!ret) {
> + pwr_state = REQ_BUS_OFF;
> + io_level = REQ_IO_LOW;
> + irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
> + } else {
> + pr_err("%s: BUS_ON req failed(%d). irq_status: 0x%08x\n",
> + mmc_hostname(mmc), ret, irq_status);
> + irq_ack |= CORE_PWRCTL_BUS_FAIL;
> + }
> }
> /* Handle IO LOW/HIGH */
> if (irq_status & CORE_PWRCTL_IO_LOW) {
> @@ -1370,6 +1465,15 @@ static void sdhci_msm_handle_pwr_irq(struct sdhci_host *host, int irq)
> irq_ack |= CORE_PWRCTL_IO_SUCCESS;
> }
>
> + if (io_level && !IS_ERR(mmc->supply.vqmmc) && !pwr_state) {
> + ret = mmc_regulator_set_vqmmc(mmc, &mmc->ios);
> + if (ret)
> + pr_err("%s: IO_level setting failed(%d). signal_voltage: %d, vdd: %d irq_status: 0x%08x\n",
> + mmc_hostname(mmc), ret,
> + mmc->ios.signal_voltage, mmc->ios.vdd,
> + irq_status);
> + }
> +
> /*
> * The driver has to acknowledge the interrupt, switch voltages and
> * report back if it succeded or not to this register. The voltage
> @@ -1605,6 +1709,91 @@ static void sdhci_msm_set_regulator_caps(struct sdhci_msm_host *msm_host)
> pr_debug("%s: supported caps: 0x%08x\n", mmc_hostname(mmc), caps);
> }
>
> +static int sdhci_msm_register_vreg(struct sdhci_msm_host *msm_host)
> +{
> + int ret = 0;
> +
> + ret = mmc_regulator_get_supply(msm_host->mmc);
> + if (ret)
> + return ret;
> + if (device_property_read_u32_array(&msm_host->pdev->dev,
> + "qcom,vmmc-current-level-microamp",
> + msm_host->vmmc_level, 2) >= 0)
> + msm_host->vmmc_load = true;
> + if (device_property_read_u32_array(&msm_host->pdev->dev,
> + "qcom,vqmmc-current-level-microamp",
> + msm_host->vqmmc_level, 2) >= 0)
> + msm_host->vqmmc_load = true;
> +
> + sdhci_msm_set_regulator_caps(msm_host);
> +
> + return 0;
> +
> +}
> +
> +static int sdhci_msm_start_signal_voltage_switch(struct mmc_host *mmc,
> + struct mmc_ios *ios)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> + u16 ctrl;
> +
> + /*
> + * Signal Voltage Switching is only applicable for Host Controllers
> + * v3.00 and above.
> + */
> + if (host->version < SDHCI_SPEC_300)
> + return 0;
> +
> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> +
> + switch (ios->signal_voltage) {
> + case MMC_SIGNAL_VOLTAGE_330:
> + if (!(host->flags & SDHCI_SIGNALING_330))
> + return -EINVAL;
> + /* Set 1.8V Signal Enable in the Host Control2 register to 0 */
> + ctrl &= ~SDHCI_CTRL_VDD_180;
> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
> +
> + /* 3.3V regulator output should be stable within 5 ms */
> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> + if (!(ctrl & SDHCI_CTRL_VDD_180))
> + return 0;
> +
> + pr_warn("%s: 3.3V regulator output did not became stable\n",
> + mmc_hostname(mmc));
> +
> + return -EAGAIN;
> + case MMC_SIGNAL_VOLTAGE_180:
> + if (!(host->flags & SDHCI_SIGNALING_180))
> + return -EINVAL;
> +
> + /*
> + * Enable 1.8V Signal Enable in the Host Control2
> + * register
> + */
> + ctrl |= SDHCI_CTRL_VDD_180;
> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
> +
> + /* 1.8V regulator output should be stable within 5 ms */
> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> + if (ctrl & SDHCI_CTRL_VDD_180)
> + return 0;
> +
> + pr_warn("%s: 1.8V regulator output did not became stable\n",
> + mmc_hostname(mmc));
> +
> + return -EAGAIN;
> + case MMC_SIGNAL_VOLTAGE_120:
> + if (!(host->flags & SDHCI_SIGNALING_120))
> + return -EINVAL;

So the state of SDHCI_CTRL_VDD_180 doesn't matter when trying to set
1.2V? I tried looking at the SDHC spec, but it was similarly silent
about 1.2V. So I guess it's fine?

> + return 0;
> + default:
> + /* No signal voltage switch required */
> + return 0;
> + }
> +
> +}
> +
> static const struct sdhci_msm_variant_ops mci_var_ops = {
> .msm_readl_relaxed = sdhci_msm_mci_variant_readl_relaxed,
> .msm_writel_relaxed = sdhci_msm_mci_variant_writel_relaxed,
> @@ -1644,6 +1833,7 @@ static void sdhci_msm_set_regulator_caps(struct sdhci_msm_host *msm_host)
> .set_uhs_signaling = sdhci_msm_set_uhs_signaling,
> .write_w = sdhci_msm_writew,
> .write_b = sdhci_msm_writeb,
> + .set_power = sdhci_set_power_noreg,
> };
>
> static const struct sdhci_pltfm_data sdhci_msm_pdata = {
> @@ -1818,6 +2008,10 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> msm_offset->core_vendor_spec_capabilities0);
> }
>
> + ret = sdhci_msm_register_vreg(msm_host);
> + if (ret)
> + goto clk_disable;
> +
> /*
> * Power on reset state may trigger power irq if previous status of
> * PWRCTL was either BUS_ON or IO_HIGH_V. So before enabling pwr irq
> @@ -1862,11 +2056,12 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> MSM_MMC_AUTOSUSPEND_DELAY_MS);
> pm_runtime_use_autosuspend(&pdev->dev);
>
> + host->mmc_host_ops.start_signal_voltage_switch =
> + sdhci_msm_start_signal_voltage_switch;
> host->mmc_host_ops.execute_tuning = sdhci_msm_execute_tuning;
> ret = sdhci_add_host(host);
> if (ret)
> goto pm_runtime_disable;
> - sdhci_msm_set_regulator_caps(msm_host);
>
> pm_runtime_mark_last_busy(&pdev->dev);
> pm_runtime_put_autosuspend(&pdev->dev);
> --
> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
>

Next message: Nicolin Chen: "[PATCH v2 0/2] Add an initial DT binding doc for ina3221"
Previous message: Evan Green: "Re: [PATCH V2 1/3] mmc: sdhci: Allow platform controlled voltage switching"
In reply to: Veerabhadrarao Badiganti: "[PATCH V2 3/3] mmc: sdhci-msm: Use internal voltage control"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]