Commit 0ac4f496 authored by Haibo Chen's avatar Haibo Chen Committed by Ulf Hansson
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mmc: sdhci-esdhc-imx: Reset before sending tuning command for manual tuning 



According to IC suggestion, everytime before sending the tuning command,
need to reset the usdhc, so to reset the tuning circuit, to let every
tuning command work well for the manual tuning method. For standard tuning
method, IC already add the reset operation in the hardware logic.

Signed-off-by: default avatarHaibo Chen <haibo.chen@nxp.com>
Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/1597135057-22272-1-git-send-email-haibo.chen@nxp.com


Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 309de450

drivers/mmc/host/sdhci-esdhc-imx.c

+10 −0
Original line number Diff line number Diff line
@@ -987,10 +987,20 @@ static int usdhc_execute_tuning(struct mmc_host *mmc, u32 opcode) 
static void esdhc_prepare_tuning(struct sdhci_host *host, u32 val)

{

	u32 reg;

	u8 sw_rst;

	int ret;



	/* FIXME: delay a bit for card to be ready for next tuning due to errors */

	mdelay(1);



	/* IC suggest to reset USDHC before every tuning command */

	esdhc_clrset_le(host, 0xff, SDHCI_RESET_ALL, SDHCI_SOFTWARE_RESET);

	ret = readb_poll_timeout(host->ioaddr + SDHCI_SOFTWARE_RESET, sw_rst,

				!(sw_rst & SDHCI_RESET_ALL), 10, 100);

	if (ret == -ETIMEDOUT)

		dev_warn(mmc_dev(host->mmc),

		"warning! RESET_ALL never complete before sending tuning command\n");



	reg = readl(host->ioaddr + ESDHC_MIX_CTRL);

	reg |= ESDHC_MIX_CTRL_EXE_TUNE | ESDHC_MIX_CTRL_SMPCLK_SEL |

			ESDHC_MIX_CTRL_FBCLK_SEL;