[PATCH 10/11] mmc: host: omap_hsmmc: remove incorrect voltage switch sequence

From: Kishon Vijay Abraham I
Date: Thu Jul 30 2015 - 03:49:22 EST


ios->vdd is set only in mmc_power_up and mmc_power_off and not in
mmc_select_voltage as mentioned in the code comment. This seems to be
legacy code that has been carried for a long time without being
tested.
This will be replaced with a proper voltage switch sequence and
populated in start_signal_voltage_switch ops to be used by
mmc core for switching voltages.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/mmc/host/omap_hsmmc.c | 81 -----------------------------------------
1 file changed, 81 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 26010a3..6b02c7c 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1325,69 +1325,6 @@ static void set_sd_bus_power(struct omap_hsmmc_host *host)
}
}

-/*
- * Switch MMC interface voltage ... only relevant for MMC1.
- *
- * MMC2 and MMC3 use fixed 1.8V levels, and maybe a transceiver.
- * The MMC2 transceiver controls are used instead of DAT4..DAT7.
- * Some chips, like eMMC ones, use internal transceivers.
- */
-static int omap_hsmmc_switch_opcond(struct omap_hsmmc_host *host, int vdd)
-{
- u32 reg_val = 0;
- int ret;
-
- /* Disable the clocks */
- pm_runtime_put_sync(host->dev);
- if (host->dbclk)
- clk_disable_unprepare(host->dbclk);
-
- /* Turn the power off */
- ret = mmc_pdata(host)->set_power(host->dev, 0, 0);
-
- /* Turn the power ON with given VDD 1.8 or 3.0v */
- if (!ret)
- ret = mmc_pdata(host)->set_power(host->dev, 1, vdd);
- pm_runtime_get_sync(host->dev);
- if (host->dbclk)
- clk_prepare_enable(host->dbclk);
-
- if (ret != 0)
- goto err;
-
- OMAP_HSMMC_WRITE(host->base, HCTL,
- OMAP_HSMMC_READ(host->base, HCTL) & SDVSCLR);
- reg_val = OMAP_HSMMC_READ(host->base, HCTL);
-
- /*
- * If a MMC dual voltage card is detected, the set_ios fn calls
- * this fn with VDD bit set for 1.8V. Upon card removal from the
- * slot, omap_hsmmc_set_ios sets the VDD back to 3V on MMC_POWER_OFF.
- *
- * Cope with a bit of slop in the range ... per data sheets:
- * - "1.8V" for vdds_mmc1/vdds_mmc1a can be up to 2.45V max,
- * but recommended values are 1.71V to 1.89V
- * - "3.0V" for vdds_mmc1/vdds_mmc1a can be up to 3.5V max,
- * but recommended values are 2.7V to 3.3V
- *
- * Board setup code shouldn't permit anything very out-of-range.
- * TWL4030-family VMMC1 and VSIM regulators are fine (avoiding the
- * middle range) but VSIM can't power DAT4..DAT7 at more than 3V.
- */
- if ((1 << vdd) <= MMC_VDD_23_24)
- reg_val |= SDVS18;
- else
- reg_val |= SDVS30;
-
- OMAP_HSMMC_WRITE(host->base, HCTL, reg_val);
- set_sd_bus_power(host);
-
- return 0;
-err:
- dev_err(mmc_dev(host->mmc), "Unable to switch operating voltage\n");
- return ret;
-}
-
/* Protect the card while the cover is open */
static void omap_hsmmc_protect_card(struct omap_hsmmc_host *host)
{
@@ -1799,24 +1736,6 @@ static void omap_hsmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

omap_hsmmc_set_bus_width(host);

- if (host->pdata->controller_flags & OMAP_HSMMC_SUPPORTS_DUAL_VOLT) {
- /* Only MMC1 can interface at 3V without some flavor
- * of external transceiver; but they all handle 1.8V.
- */
- if ((OMAP_HSMMC_READ(host->base, HCTL) & SDVSDET) &&
- (ios->vdd == DUAL_VOLT_OCR_BIT)) {
- /*
- * The mmc_select_voltage fn of the core does
- * not seem to set the power_mode to
- * MMC_POWER_UP upon recalculating the voltage.
- * vdd 1.8v.
- */
- if (omap_hsmmc_switch_opcond(host, ios->vdd) != 0)
- dev_dbg(mmc_dev(host->mmc),
- "Switch operation failed\n");
- }
- }
-
omap_hsmmc_set_clock(host);

if (ios->timing != host->timing) {
--
1.7.9.5

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