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mmc: sdhci_am654: Add sdhci_am654_start_signal_voltage_switch

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The sdhci_start_signal_voltage_switch function sets
V1P8_SIGNAL_ENA by default after switching to 1v8 signaling.
V1P8_SIGNAL_ENA determines whether to launch cmd/data on neg
edge or pos edge of clock.

Due to some eMMC and SD failures seen across am62x platform,
do not set V1P8_SIGNAL_ENA by default, only enable the bit
for devices that require this bit in order to switch to 1v8
voltage for uhs modes.

Signed-off-by: Judith Mendez <jm@ti.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20240913185403.1339115-1-jm@ti.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Judith Mendez 2024-09-13 13:54:03 -05:00 committed by Ulf Hansson
parent cd068d5159
commit 941a7abd46
1 changed files with 30 additions and 0 deletions
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30
drivers/mmc/host/sdhci_am654.c
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@ -155,6 +155,7 @@ struct sdhci_am654_data {
u32 tuning_loop;
#define SDHCI_AM654_QUIRK_FORCE_CDTEST BIT(0)
#define SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA BIT(1)
};
struct window {
@ -356,6 +357,29 @@ static void sdhci_j721e_4bit_set_clock(struct sdhci_host *host,
sdhci_set_clock(host, clock);
}
static int sdhci_am654_start_signal_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct sdhci_host *host = mmc_priv(mmc);
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
int ret;
if ((sdhci_am654->quirks & SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA) &&
ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
if (!IS_ERR(mmc->supply.vqmmc)) {
ret = mmc_regulator_set_vqmmc(mmc, ios);
if (ret < 0) {
pr_err("%s: Switching to 1.8V signalling voltage failed,\n",
mmc_hostname(mmc));
return -EIO;
}
}
return 0;
}
return sdhci_start_signal_voltage_switch(mmc, ios);
}
static u8 sdhci_am654_write_power_on(struct sdhci_host *host, u8 val, int reg)
{
writeb(val, host->ioaddr + reg);
@ -844,6 +868,11 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
if (device_property_read_bool(dev, "ti,fails-without-test-cd"))
sdhci_am654->quirks |= SDHCI_AM654_QUIRK_FORCE_CDTEST;
/* Suppress v1p8 ena for eMMC and SD with vqmmc supply */
if (!!of_parse_phandle(dev->of_node, "vmmc-supply", 0) ==
!!of_parse_phandle(dev->of_node, "vqmmc-supply", 0))
sdhci_am654->quirks |= SDHCI_AM654_QUIRK_SUPPRESS_V1P8_ENA;
sdhci_get_of_property(pdev);
return 0;
@ -940,6 +969,7 @@ static int sdhci_am654_probe(struct platform_device *pdev)
goto err_pltfm_free;
}
host->mmc_host_ops.start_signal_voltage_switch = sdhci_am654_start_signal_voltage_switch;
host->mmc_host_ops.execute_tuning = sdhci_am654_execute_tuning;
pm_runtime_get_noresume(dev);