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mmc: sdhci-omap: Add card_busy host ops

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Add card_busy host ops in sdhci_omap to check card busy status.

The voltage switching sequence for AM572x platform is mentioned
in Figure 25-48. eMMC/SD/SDIO Power Switching Procedure of
AM572x Sitara Processors Silicon Revision 2.0, 1.1 TRM
(SPRUHZ6I - October 2014–Revised April 2017 [1]).

In the voltage switching sequence, CLKEXTFREE bit in MMCHS_CON
should also be set after switching to 1.8v which is also taken
care in the card_busy ops.

[1] -> http://www.ti.com/lit/ug/spruhz6i/spruhz6i.pdf

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Kishon Vijay Abraham I 2018-02-05 18:20:15 +05:30 committed by Ulf Hansson
parent 300df508c8
commit 20ea26a1e3
1 changed files with 52 additions and 0 deletions
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52
drivers/mmc/host/sdhci-omap.c
View File

@ -31,11 +31,17 @@
#define SDHCI_OMAP_CON 0x12c
#define CON_DW8 BIT(5)
#define CON_DMA_MASTER BIT(20)
#define CON_CLKEXTFREE BIT(16)
#define CON_PADEN BIT(15)
#define CON_INIT BIT(1)
#define CON_OD BIT(0)
#define SDHCI_OMAP_CMD 0x20c
#define SDHCI_OMAP_PSTATE 0x0224
#define PSTATE_DLEV_DAT0 BIT(20)
#define PSTATE_DATI BIT(1)
#define SDHCI_OMAP_HCTL 0x228
#define HCTL_SDBP BIT(8)
#define HCTL_SDVS_SHIFT 9
@ -191,6 +197,51 @@ static void sdhci_omap_conf_bus_power(struct sdhci_omap_host *omap_host,
}
}
static int sdhci_omap_card_busy(struct mmc_host *mmc)
{
u32 reg, ac12;
int ret = false;
struct sdhci_host *host = mmc_priv(mmc);
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_omap_host *omap_host;
u32 ier = host->ier;
pltfm_host = sdhci_priv(host);
omap_host = sdhci_pltfm_priv(pltfm_host);
reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_CON);
ac12 = sdhci_omap_readl(omap_host, SDHCI_OMAP_AC12);
reg &= ~CON_CLKEXTFREE;
if (ac12 & AC12_V1V8_SIGEN)
reg |= CON_CLKEXTFREE;
reg |= CON_PADEN;
sdhci_omap_writel(omap_host, SDHCI_OMAP_CON, reg);
disable_irq(host->irq);
ier |= SDHCI_INT_CARD_INT;
sdhci_writel(host, ier, SDHCI_INT_ENABLE);
sdhci_writel(host, ier, SDHCI_SIGNAL_ENABLE);
/*
* Delay is required for PSTATE to correctly reflect
* DLEV/CLEV values after PADEN is set.
*/
usleep_range(50, 100);
reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_PSTATE);
if ((reg & PSTATE_DATI) || !(reg & PSTATE_DLEV_DAT0))
ret = true;
reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_CON);
reg &= ~(CON_CLKEXTFREE | CON_PADEN);
sdhci_omap_writel(omap_host, SDHCI_OMAP_CON, reg);
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
enable_irq(host->irq);
return ret;
}
static int sdhci_omap_start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios)
{
@ -562,6 +613,7 @@ static int sdhci_omap_probe(struct platform_device *pdev)
host->mmc_host_ops.start_signal_voltage_switch =
sdhci_omap_start_signal_voltage_switch;
host->mmc_host_ops.set_ios = sdhci_omap_set_ios;
host->mmc_host_ops.card_busy = sdhci_omap_card_busy;
sdhci_read_caps(host);
host->caps |= SDHCI_CAN_DO_ADMA2;