mfd: arizona: Add a hardware patch mechanism

This patch adds facilities for apply a register patch contained within
the chip using the write sequencer.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 109 insertions, 0 deletions

diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c
index b09b119d4966..d6b40df64c4a 100644
--- a/drivers/mfd/arizona-core.c
+++ b/drivers/mfd/arizona-core.c
@@ -242,6 +242,90 @@ static int arizona_wait_for_boot(struct arizona *arizona)
         return ret;
 }
 
+static int arizona_apply_hardware_patch(struct arizona* arizona)
+{
+        unsigned int fll, sysclk;
+        int ret, err;
+
+        regcache_cache_bypass(arizona->regmap, true);
+
+        /* Cache existing FLL and SYSCLK settings */
+        ret = regmap_read(arizona->regmap, ARIZONA_FLL1_CONTROL_1, &fll);
+        if (ret != 0) {
+                dev_err(arizona->dev, "Failed to cache FLL settings: %d\n",
+                        ret);
+                return ret;
+        }
+        ret = regmap_read(arizona->regmap, ARIZONA_SYSTEM_CLOCK_1, &sysclk);
+        if (ret != 0) {
+                dev_err(arizona->dev, "Failed to cache SYSCLK settings: %d\n",
+                        ret);
+                return ret;
+        }
+
+        /* Start up SYSCLK using the FLL in free running mode */
+        ret = regmap_write(arizona->regmap, ARIZONA_FLL1_CONTROL_1,
+                        ARIZONA_FLL1_ENA | ARIZONA_FLL1_FREERUN);
+        if (ret != 0) {
+                dev_err(arizona->dev,
+                        "Failed to start FLL in freerunning mode: %d\n",
+                        ret);
+                return ret;
+        }
+        ret = arizona_poll_reg(arizona, 25, ARIZONA_INTERRUPT_RAW_STATUS_5,
+                               ARIZONA_FLL1_CLOCK_OK_STS,
+                               ARIZONA_FLL1_CLOCK_OK_STS);
+        if (ret != 0) {
+                ret = -ETIMEDOUT;
+                goto err_fll;
+        }
+
+        ret = regmap_write(arizona->regmap, ARIZONA_SYSTEM_CLOCK_1, 0x0144);
+        if (ret != 0) {
+                dev_err(arizona->dev, "Failed to start SYSCLK: %d\n", ret);
+                goto err_fll;
+        }
+
+        /* Start the write sequencer and wait for it to finish */
+        ret = regmap_write(arizona->regmap, ARIZONA_WRITE_SEQUENCER_CTRL_0,
+                        ARIZONA_WSEQ_ENA | ARIZONA_WSEQ_START | 160);
+        if (ret != 0) {
+                dev_err(arizona->dev, "Failed to start write sequencer: %d\n",
+                        ret);
+                goto err_sysclk;
+        }
+        ret = arizona_poll_reg(arizona, 5, ARIZONA_WRITE_SEQUENCER_CTRL_1,
+                               ARIZONA_WSEQ_BUSY, 0);
+        if (ret != 0) {
+                regmap_write(arizona->regmap, ARIZONA_WRITE_SEQUENCER_CTRL_0,
+                                ARIZONA_WSEQ_ABORT);
+                ret = -ETIMEDOUT;
+        }
+
+err_sysclk:
+        err = regmap_write(arizona->regmap, ARIZONA_SYSTEM_CLOCK_1, sysclk);
+        if (err != 0) {
+                dev_err(arizona->dev,
+                        "Failed to re-apply old SYSCLK settings: %d\n",
+                        err);
+        }
+
+err_fll:
+        err = regmap_write(arizona->regmap, ARIZONA_FLL1_CONTROL_1, fll);
+        if (err != 0) {
+                dev_err(arizona->dev,
+                        "Failed to re-apply old FLL settings: %d\n",
+                        err);
+        }
+
+        regcache_cache_bypass(arizona->regmap, false);
+
+        if (ret != 0)
+                return ret;
+        else
+                return err;
+}
+
 #ifdef CONFIG_PM_RUNTIME
 static int arizona_runtime_resume(struct device *dev)
 {
@@ -271,6 +355,17 @@ static int arizona_runtime_resume(struct device *dev)
                                 ret);
                         goto err;
                 }
+
+                ret = arizona_apply_hardware_patch(arizona);
+                if (ret != 0) {
+                        dev_err(arizona->dev,
+                                "Failed to apply hardware patch: %d\n",
+                                ret);
+                        goto err;
+                }
+                break;
+        default:
+                break;
         }
 
         ret = regcache_sync(arizona->regmap);
@@ -513,6 +608,20 @@ int arizona_dev_init(struct arizona *arizona)
                                 ret);
                         goto err_reset;
                 }
+
+                switch (arizona->type) {
+                case WM5102:
+                        ret = arizona_apply_hardware_patch(arizona);
+                        if (ret != 0) {
+                                dev_err(arizona->dev,
+                                        "Failed to apply hardware patch: %d\n",
+                                        ret);
+                                goto err_reset;
+                        }
+                        break;
+                default:
+                        break;
+                }
         }
 
         for (i = 0; i < ARRAY_SIZE(arizona->pdata.gpio_defaults); i++) {