From 6b11e70bb72c5bfbd7d1544518d26d4b1100aae1 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 2 Dec 2016 15:14:27 +0200 Subject: [PATCH] mmc: sdhci: Tidy tuning loop Tidy the tuning loop by moving it to a separate function and making it a for-loop. Signed-off-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci.c | 81 +++++++++++++++++++++------------------- 1 file changed, 43 insertions(+), 38 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 6fdec4ad4ad4..2b89fb9e9a6b 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2062,11 +2062,47 @@ static void sdhci_send_tuning(struct sdhci_host *host, u32 opcode, spin_lock_irqsave(&host->lock, flags); } +static void __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode, + unsigned long flags) +{ + int i; + + /* + * Issue opcode repeatedly till Execute Tuning is set to 0 or the number + * of loops reaches 40 times. + */ + for (i = 0; i < MAX_TUNING_LOOP; i++) { + u16 ctrl; + + sdhci_send_tuning(host, opcode, flags); + + if (!host->tuning_done) { + pr_info("%s: Tuning timeout, falling back to fixed sampling clock\n", + mmc_hostname(host->mmc)); + sdhci_abort_tuning(host, opcode, flags); + return; + } + + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); + if (!(ctrl & SDHCI_CTRL_EXEC_TUNING)) { + if (ctrl & SDHCI_CTRL_TUNED_CLK) + return; /* Success! */ + break; + } + + /* eMMC spec does not require a delay between tuning cycles */ + if (opcode == MMC_SEND_TUNING_BLOCK) + mdelay(1); + } + + pr_info("%s: Tuning failed, falling back to fixed sampling clock\n", + mmc_hostname(host->mmc)); + sdhci_reset_tuning(host); +} + static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) { struct sdhci_host *host = mmc_priv(mmc); - u16 ctrl; - int tuning_loop_counter = MAX_TUNING_LOOP; int err = 0; unsigned long flags; unsigned int tuning_count = 0; @@ -2117,50 +2153,19 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) if (host->ops->platform_execute_tuning) { spin_unlock_irqrestore(&host->lock, flags); - err = host->ops->platform_execute_tuning(host, opcode); - return err; + return host->ops->platform_execute_tuning(host, opcode); } - sdhci_start_tuning(host); - - /* - * Issue CMD19 repeatedly till Execute Tuning is set to 0 or the number - * of loops reaches 40 times. - */ - do { - if (tuning_loop_counter-- == 0) - break; - - sdhci_send_tuning(host, opcode, flags); - - if (!host->tuning_done) { - pr_info(DRIVER_NAME ": Timeout waiting for Buffer Read Ready interrupt during tuning procedure, falling back to fixed sampling clock\n"); - sdhci_abort_tuning(host, opcode, flags); - goto out; - } - - ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); - - /* eMMC spec does not require a delay between tuning cycles */ - if (opcode == MMC_SEND_TUNING_BLOCK) - mdelay(1); - } while (ctrl & SDHCI_CTRL_EXEC_TUNING); + host->mmc->retune_period = tuning_count; - /* - * The Host Driver has exhausted the maximum number of loops allowed, - * so use fixed sampling frequency. - */ - if (tuning_loop_counter < 0) - sdhci_reset_tuning(host); + sdhci_start_tuning(host); - if (tuning_loop_counter < 0 || !(ctrl & SDHCI_CTRL_TUNED_CLK)) - pr_info(DRIVER_NAME ": Tuning procedure failed, falling back to fixed sampling clock\n"); -out: - host->mmc->retune_period = tuning_count; + __sdhci_execute_tuning(host, opcode, flags); sdhci_end_tuning(host); out_unlock: spin_unlock_irqrestore(&host->lock, flags); + return err; } -- 2.20.1