On Thu 21 May 08:23 PDT 2020, Veerabhadrarao Badiganti wrote:
> On qcom SD host controllers 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 internal voltage switching and then control the voltage
> switching using power irq.
>
> Set the regulator load as well so that regulator can be configured
> in LPM mode when in is not being used.
>
> Co-developed-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
> Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
> Co-developed-by: Vijay Viswanath <vviswana@xxxxxxxxxxxxxx>
> Signed-off-by: Vijay Viswanath <vviswana@xxxxxxxxxxxxxx>
> Co-developed-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>
> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@xxxxxxxxxxxxxx>
Looks better, thanks.
> ---
> drivers/mmc/host/sdhci-msm.c | 207 +++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 198 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
[..]
> static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host)
> @@ -1298,6 +1302,71 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host,
> sdhci_msm_hs400(host, &mmc->ios);
> }
>
> +static int sdhci_msm_set_vmmc(struct mmc_host *mmc)
> +{
> + int ret;
> +
> + if (IS_ERR(mmc->supply.vmmc))
> + return 0;
> +
> + ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd);
> + if (ret)
> + dev_err(mmc_dev(mmc), "%s: vmmc set ocr with vdd=%d failed: %d\n",
> + mmc_hostname(mmc), mmc->ios.vdd, ret);
Missed this one on v1, in the event that mmc_regulator_set_ocr() return
a non-zero value it has already printed an error message. So please
replace the tail with just:
return mmc_regulator_set_ocr(...);
> +
> + return ret;
> +}
> +
> +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host,
> + struct mmc_host *mmc, bool level)
> +{
> + int load, ret;
> + struct mmc_ios ios;
> +
> + if (IS_ERR(mmc->supply.vqmmc) ||
> + (mmc->ios.power_mode == MMC_POWER_UNDEFINED) ||
> + (msm_host->vqmmc_enabled == level))
> + return 0;
> +
> + if (msm_host->vqmmc_load) {
> + load = level ? msm_host->vqmmc_load : 0;
> + ret = regulator_set_load(mmc->supply.vqmmc, load);
Sorry for the late reply on v1, but please see my explanation regarding
load and always-on regulators there.
> + if (ret) {
> + dev_err(mmc_dev(mmc), "%s: vqmmc set load failed: %d\n",
> + mmc_hostname(mmc), ret);
> + goto out;
> + }
> + }
> +
> + if (level) {
> + /* Set the IO voltage regulator to default voltage 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) {
> + ret = mmc_regulator_set_vqmmc(mmc, &ios);
> + if (ret < 0) {
> + dev_err(mmc_dev(mmc), "%s: vqmmc set volgate failed: %d\n",
> + mmc_hostname(mmc), ret);
> + goto out;
> + }
> + }
> + ret = regulator_enable(mmc->supply.vqmmc);
> + } else {
> + ret = regulator_disable(mmc->supply.vqmmc);
> + }
> +
> + if (ret)
> + dev_err(mmc_dev(mmc), "%s: vqmm %sable failed: %d\n",
> + mmc_hostname(mmc), level ? "en":"dis", ret);
> + else
> + msm_host->vqmmc_enabled = level;
> +out:
> + return ret;
> +}
[..]
> +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, status;
> +
> + /*
> + * 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;
> + break;
> + 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;
> + break;
> + case MMC_SIGNAL_VOLTAGE_120:
> + if (!(host->flags & SDHCI_SIGNALING_120))
> + return -EINVAL;
> + return 0;
> + default:
> + /* No signal voltage switch required */
> + return 0;
> + }
> +
> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
> +
> + /* Wait for 5ms */
> + usleep_range(5000, 5500);
> +
> + /* regulator output should be stable within 5 ms */
> + status = !!(ctrl & SDHCI_CTRL_VDD_180);
> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> + if (!!(ctrl & SDHCI_CTRL_VDD_180) == status)
You should be able to drop the !! both here and when assigning status.
Overall this looks neater, thanks for reworking it.
Regards,
Bjorn
