On 20/07/18 13:46, Vijay Viswanath wrote:
> Some controllers can have internal mechanism to inform the SW that it
> is ready for voltage switching. For such controllers, changing voltage
> before the HW is ready can result in various issues.
>
> During setup/cleanup of host, check whether regulator enable/disable
> was already done by platform driver.
>
> Signed-off-by: Vijay Viswanath <vvisw...@codeaurora.org>
> ---
> drivers/mmc/host/sdhci.c | 21 ++++++++++++++++-----
> 1 file changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 1c828e0..494a1e2 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -3472,6 +3472,7 @@ int sdhci_setup_host(struct sdhci_host *host)
> unsigned int override_timeout_clk;
> u32 max_clk;
> int ret;
> + bool enable_vqmmc = false;
>
> WARN_ON(host == NULL);
> if (host == NULL)
> @@ -3485,7 +3486,12 @@ int sdhci_setup_host(struct sdhci_host *host)
> * the host can take the appropriate action if regulators are not
> * available.
> */
> - ret = mmc_regulator_get_supply(mmc);
> + if (!mmc->supply.vmmc) {
> + ret = mmc_regulator_get_supply(mmc);
> + enable_vqmmc = true;
> + } else {
> + ret = 0;
> + }
> if (ret)
> return ret;
Why not
if (!mmc->supply.vmmc) {
ret = mmc_regulator_get_supply(mmc);
if (ret)
return ret;
enable_vqmmc = true;
}
>
> @@ -3736,7 +3742,10 @@ int sdhci_setup_host(struct sdhci_host *host)
>
> /* If vqmmc regulator and no 1.8V signalling, then there's no UHS */
> if (!IS_ERR(mmc->supply.vqmmc)) {
> - ret = regulator_enable(mmc->supply.vqmmc);
> + if (enable_vqmmc)
> + ret = regulator_enable(mmc->supply.vqmmc);
Please introduce host->vqmmc_enabled = !ret;
> + else
> + ret = 0;
> if (!regulator_is_supported_voltage(mmc->supply.vqmmc, 1700000,
> 1950000))
> host->caps1 &= ~(SDHCI_SUPPORT_SDR104 |
> @@ -3984,7 +3993,7 @@ int sdhci_setup_host(struct sdhci_host *host)
> return 0;
>
> unreg:
> - if (!IS_ERR(mmc->supply.vqmmc))
> + if (!IS_ERR(mmc->supply.vqmmc) && enable_vqmmc)
And just make this
if (host->vqmmc_enabled)
> regulator_disable(mmc->supply.vqmmc);
> undma:
> if (host->align_buffer)
> @@ -4002,7 +4011,8 @@ void sdhci_cleanup_host(struct sdhci_host *host)
> {
> struct mmc_host *mmc = host->mmc;
>
> - if (!IS_ERR(mmc->supply.vqmmc))
> + if (!IS_ERR(mmc->supply.vqmmc) &&
> + (regulator_is_enabled(mmc->supply.vqmmc) > 0))
if (host->vqmmc_enabled)
> regulator_disable(mmc->supply.vqmmc);
>
> if (host->align_buffer)
> @@ -4135,7 +4145,8 @@ void sdhci_remove_host(struct sdhci_host *host, int
> dead)
>
> tasklet_kill(&host->finish_tasklet);
>
> - if (!IS_ERR(mmc->supply.vqmmc))
> + if (!IS_ERR(mmc->supply.vqmmc) &&
> + (regulator_is_enabled(mmc->supply.vqmmc) > 0))
if (host->vqmmc_enabled)
> regulator_disable(mmc->supply.vqmmc);
>
> if (host->align_buffer)
>
