ASoC: Intel: cht_bsw_rt5672: 19.2MHz clock for Baytrail platforms

Lenovo platforms use RT5670 with Baytrail, add the required
MCLK control and configuration to 19.2MHz

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=96691
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/boards/cht_bsw_rt5672.c b/sound/soc/intel/boards/cht_bsw_rt5672.c
index e4d46d4360d7e88cfdac008e9804bb7fdb310e6f..bc2a52de06a39729ac6aae83c38e08e822575445 100644 (file)
--- a/sound/soc/intel/boards/cht_bsw_rt5672.c
+++ b/sound/soc/intel/boards/cht_bsw_rt5672.c
@@ -19,6 +19,8 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/clk.h>
+#include <asm/cpu_device_id.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
@@ -31,8 +33,11 @@
 #define CHT_PLAT_CLK_3_HZ      19200000
 #define CHT_CODEC_DAI  "rt5670-aif1"
 
-static struct snd_soc_jack cht_bsw_headset;
-static char cht_bsw_codec_name[16];
+struct cht_mc_private {
+       struct snd_soc_jack headset;
+       char codec_name[16];
+       struct clk *mclk;
+};
 
 /* Headset jack detection DAPM pins */
 static struct snd_soc_jack_pin cht_bsw_headset_pins[] = {
@@ -64,6 +69,7 @@ static int platform_clock_control(struct snd_soc_dapm_widget *w,
        struct snd_soc_dapm_context *dapm = w->dapm;
        struct snd_soc_card *card = dapm->card;
        struct snd_soc_dai *codec_dai;
+       struct cht_mc_private *ctx = snd_soc_card_get_drvdata(card);
        int ret;
 
        codec_dai = cht_get_codec_dai(card);
@@ -73,6 +79,15 @@ static int platform_clock_control(struct snd_soc_dapm_widget *w,
        }
 
        if (SND_SOC_DAPM_EVENT_ON(event)) {
+               if (ctx->mclk) {
+                       ret = clk_prepare_enable(ctx->mclk);
+                       if (ret < 0) {
+                               dev_err(card->dev,
+                                       "could not configure MCLK state");
+                               return ret;
+                       }
+               }
+
                /* set codec PLL source to the 19.2MHz platform clock (MCLK) */
                ret = snd_soc_dai_set_pll(codec_dai, 0, RT5670_PLL1_S_MCLK,
                                CHT_PLAT_CLK_3_HZ, 48000 * 512);
@@ -96,6 +111,9 @@ static int platform_clock_control(struct snd_soc_dapm_widget *w,
                 */
                snd_soc_dai_set_sysclk(codec_dai, RT5670_SCLK_S_RCCLK,
                                       48000 * 512, SND_SOC_CLOCK_IN);
+
+               if (ctx->mclk)
+                       clk_disable_unprepare(ctx->mclk);
        }
        return 0;
 }
@@ -171,6 +189,7 @@ static int cht_codec_init(struct snd_soc_pcm_runtime *runtime)
        int ret;
        struct snd_soc_dai *codec_dai = runtime->codec_dai;
        struct snd_soc_codec *codec = codec_dai->codec;
+       struct cht_mc_private *ctx = snd_soc_card_get_drvdata(runtime->card);
 
        /* TDM 4 slots 24 bit, set Rx & Tx bitmask to 4 active slots */
        ret = snd_soc_dai_set_tdm_slot(codec_dai, 0xF, 0xF, 4, 24);
@@ -194,13 +213,37 @@ static int cht_codec_init(struct snd_soc_pcm_runtime *runtime)
                                RT5670_CLK_SEL_I2S1_ASRC);
 
         ret = snd_soc_card_jack_new(runtime->card, "Headset",
-                SND_JACK_HEADSET | SND_JACK_BTN_0 |
-                SND_JACK_BTN_1 | SND_JACK_BTN_2, &cht_bsw_headset,
-                cht_bsw_headset_pins, ARRAY_SIZE(cht_bsw_headset_pins));
+                                   SND_JACK_HEADSET | SND_JACK_BTN_0 |
+                                   SND_JACK_BTN_1 | SND_JACK_BTN_2,
+                                   &ctx->headset,
+                                   cht_bsw_headset_pins,
+                                   ARRAY_SIZE(cht_bsw_headset_pins));
         if (ret)
                 return ret;
 
-       rt5670_set_jack_detect(codec, &cht_bsw_headset);
+       rt5670_set_jack_detect(codec, &ctx->headset);
+       if (ctx->mclk) {
+               /*
+                * The firmware might enable the clock at
+                * boot (this information may or may not
+                * be reflected in the enable clock register).
+                * To change the rate we must disable the clock
+                * first to cover these cases. Due to common
+                * clock framework restrictions that do not allow
+                * to disable a clock that has not been enabled,
+                * we need to enable the clock first.
+                */
+               ret = clk_prepare_enable(ctx->mclk);
+               if (!ret)
+                       clk_disable_unprepare(ctx->mclk);
+
+               ret = clk_set_rate(ctx->mclk, CHT_PLAT_CLK_3_HZ);
+
+               if (ret) {
+                       dev_err(runtime->dev, "unable to set MCLK rate\n");
+                       return ret;
+               }
+       }
        return 0;
 }
 
@@ -341,34 +384,62 @@ static struct snd_soc_card snd_soc_card_cht = {
        .resume_post = cht_resume_post,
 };
 
+static bool is_valleyview(void)
+{
+       static const struct x86_cpu_id cpu_ids[] = {
+               { X86_VENDOR_INTEL, 6, 55 }, /* Valleyview, Bay Trail */
+               {}
+       };
+
+       if (!x86_match_cpu(cpu_ids))
+               return false;
+       return true;
+}
+
 #define RT5672_I2C_DEFAULT     "i2c-10EC5670:00"
 
 static int snd_cht_mc_probe(struct platform_device *pdev)
 {
        int ret_val = 0;
+       struct cht_mc_private *drv;
        struct sst_acpi_mach *mach = pdev->dev.platform_data;
        const char *i2c_name;
        int i;
 
-       strcpy(cht_bsw_codec_name, RT5672_I2C_DEFAULT);
+       drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_ATOMIC);
+       if (!drv)
+               return -ENOMEM;
+
+       strcpy(drv->codec_name, RT5672_I2C_DEFAULT);
 
        /* fixup codec name based on HID */
        if (mach) {
                i2c_name = sst_acpi_find_name_from_hid(mach->id);
                if (i2c_name) {
-                       snprintf(cht_bsw_codec_name, sizeof(cht_bsw_codec_name),
+                       snprintf(drv->codec_name, sizeof(drv->codec_name),
                                 "i2c-%s", i2c_name);
                        for (i = 0; i < ARRAY_SIZE(cht_dailink); i++) {
                                if (!strcmp(cht_dailink[i].codec_name,
                                            RT5672_I2C_DEFAULT)) {
                                        cht_dailink[i].codec_name =
-                                               cht_bsw_codec_name;
+                                               drv->codec_name;
                                        break;
                                }
                        }
                }
        }
 
+       if (is_valleyview()) {
+               drv->mclk = devm_clk_get(&pdev->dev, "pmc_plt_clk_3");
+               if (IS_ERR(drv->mclk)) {
+                       dev_err(&pdev->dev,
+                               "Failed to get MCLK from pmc_plt_clk_3: %ld\n",
+                               PTR_ERR(drv->mclk));
+                       return PTR_ERR(drv->mclk);
+               }
+       }
+       snd_soc_card_set_drvdata(&snd_soc_card_cht, drv);
+
        /* register the soc card */
        snd_soc_card_cht.dev = &pdev->dev;
        ret_val = devm_snd_soc_register_card(&pdev->dev, &snd_soc_card_cht);