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 <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files 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;
 }