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mmc: sdhci: Tidy tuning loop

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Tidy the tuning loop by moving it to a separate function and making it a
for-loop.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Adrian Hunter 2016-12-02 15:14:27 +02:00 committed by Ulf Hansson
parent 85336109c0
commit 6b11e70bb7
1 changed files with 43 additions and 38 deletions
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81
drivers/mmc/host/sdhci.c
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@ -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);
}
host->mmc->retune_period = tuning_count;
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);
/*
* 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);
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;
}