ASoC: fsl_sai: Add pm qos cpu latency support

On SoCs such as i.MX7ULP, cpuidle has some levels which
may disable system/bus clocks, so need to add pm_qos to
prevent cpuidle from entering low level idles and make sure
system/bus clocks are enabled when sai is active.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1613983220-5373-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index 5e65b45..a22679d 100644 (file)
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
+#include <linux/pm_qos.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
@@ -1177,6 +1178,7 @@ static const struct fsl_sai_soc_data fsl_sai_vf610_data = {
        .fifo_depth = 32,
        .reg_offset = 0,
        .mclk0_is_mclk1 = false,
+       .flags = 0,
 };
 
 static const struct fsl_sai_soc_data fsl_sai_imx6sx_data = {
@@ -1185,6 +1187,7 @@ static const struct fsl_sai_soc_data fsl_sai_imx6sx_data = {
        .fifo_depth = 32,
        .reg_offset = 0,
        .mclk0_is_mclk1 = true,
+       .flags = 0,
 };
 
 static const struct fsl_sai_soc_data fsl_sai_imx7ulp_data = {
@@ -1193,6 +1196,7 @@ static const struct fsl_sai_soc_data fsl_sai_imx7ulp_data = {
        .fifo_depth = 16,
        .reg_offset = 8,
        .mclk0_is_mclk1 = false,
+       .flags = PMQOS_CPU_LATENCY,
 };
 
 static const struct fsl_sai_soc_data fsl_sai_imx8mq_data = {
@@ -1201,6 +1205,7 @@ static const struct fsl_sai_soc_data fsl_sai_imx8mq_data = {
        .fifo_depth = 128,
        .reg_offset = 8,
        .mclk0_is_mclk1 = false,
+       .flags = 0,
 };
 
 static const struct fsl_sai_soc_data fsl_sai_imx8qm_data = {
@@ -1209,6 +1214,7 @@ static const struct fsl_sai_soc_data fsl_sai_imx8qm_data = {
        .fifo_depth = 64,
        .reg_offset = 0,
        .mclk0_is_mclk1 = false,
+       .flags = 0,
 };
 
 static const struct of_device_id fsl_sai_ids[] = {
@@ -1235,6 +1241,9 @@ static int fsl_sai_runtime_suspend(struct device *dev)
 
        clk_disable_unprepare(sai->bus_clk);
 
+       if (sai->soc_data->flags & PMQOS_CPU_LATENCY)
+               cpu_latency_qos_remove_request(&sai->pm_qos_req);
+
        regcache_cache_only(sai->regmap, true);
 
        return 0;
@@ -1264,6 +1273,9 @@ static int fsl_sai_runtime_resume(struct device *dev)
                        goto disable_tx_clk;
        }
 
+       if (sai->soc_data->flags & PMQOS_CPU_LATENCY)
+               cpu_latency_qos_add_request(&sai->pm_qos_req, 0);
+
        regcache_cache_only(sai->regmap, false);
        regcache_mark_dirty(sai->regmap);
        regmap_write(sai->regmap, FSL_SAI_TCSR(ofs), FSL_SAI_CSR_SR);

diff --git a/sound/soc/fsl/fsl_sai.h b/sound/soc/fsl/fsl_sai.h
index ff2619f..bc60030 100644 (file)
--- a/sound/soc/fsl/fsl_sai.h
+++ b/sound/soc/fsl/fsl_sai.h
@@ -216,12 +216,15 @@
 #define FSL_SAI_MAXBURST_TX 6
 #define FSL_SAI_MAXBURST_RX 6
 
+#define PMQOS_CPU_LATENCY   BIT(0)
+
 struct fsl_sai_soc_data {
        bool use_imx_pcm;
        bool use_edma;
        bool mclk0_is_mclk1;
        unsigned int fifo_depth;
        unsigned int reg_offset;
+       unsigned int flags;
 };
 
 /**
@@ -273,6 +276,7 @@ struct fsl_sai {
        struct snd_dmaengine_dai_dma_data dma_params_tx;
        struct fsl_sai_verid verid;
        struct fsl_sai_param param;
+       struct pm_qos_request pm_qos_req;
 };
 
 #define TX 1