Re: [PATCH v3 1/3] soundwire: qcom: add runtime pm support

On 2/28/22 11:25, Srinivas Kandagatla wrote:

Add support to runtime PM using SoundWire clock stop Mode0 on supported controller instances and soft reset on instances that do not support clock stop.

Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org

Reviewed-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

---

drivers/soundwire/qcom.c | 156 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 155 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index 54813417ef8e..810232686196 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -11,6 +11,7 @@ #include <linux/of.h> #include <linux/of_irq.h> #include <linux/of_device.h> +#include <linux/pm_runtime.h> #include <linux/regmap.h> #include <linux/slab.h> #include <linux/slimbus.h> @@ -20,6 +21,9 @@ #include <sound/soc.h> #include "bus.h"

+#define SWRM_COMP_SW_RESET 0x008 +#define SWRM_COMP_STATUS 0x014 +#define SWRM_FRM_GEN_ENABLED BIT(0) #define SWRM_COMP_HW_VERSION 0x00 #define SWRM_COMP_CFG_ADDR 0x04 #define SWRM_COMP_CFG_IRQ_LEVEL_OR_PULSE_MSK BIT(1) @@ -29,6 +33,7 @@ #define SWRM_COMP_PARAMS_RD_FIFO_DEPTH GENMASK(19, 15) #define SWRM_COMP_PARAMS_DOUT_PORTS_MASK GENMASK(4, 0) #define SWRM_COMP_PARAMS_DIN_PORTS_MASK GENMASK(9, 5) +#define SWRM_COMP_MASTER_ID 0x104 #define SWRM_INTERRUPT_STATUS 0x200 #define SWRM_INTERRUPT_STATUS_RMSK GENMASK(16, 0) #define SWRM_INTERRUPT_STATUS_SLAVE_PEND_IRQ BIT(0) @@ -111,6 +116,13 @@ #define SWR_MAX_CMD_ID 14 #define MAX_FIFO_RD_RETRY 3 #define SWR_OVERFLOW_RETRY_COUNT 30 +#define SWRM_LINK_STATUS_RETRY_CNT 100

+enum {

• MASTER_ID_WSA = 1,
• MASTER_ID_RX,
• MASTER_ID_TX

+};

struct qcom_swrm_port_config { u8 si; @@ -159,6 +171,7 @@ struct qcom_swrm_ctrl { u32 slave_status; u32 wr_fifo_depth; u32 rd_fifo_depth;

• bool clock_stop_not_supported;

};

struct qcom_swrm_data { @@ -497,6 +510,7 @@ static irqreturn_t qcom_swrm_irq_handler(int irq, void *dev_id) u32 i; int devnum; int ret = IRQ_HANDLED;

• clk_prepare_enable(swrm->hclk);

  swrm->reg_read(swrm, SWRM_INTERRUPT_STATUS, &intr_sts); intr_sts_masked = intr_sts & swrm->intr_mask;

@@ -604,6 +618,7 @@ static irqreturn_t qcom_swrm_irq_handler(int irq, void *dev_id) intr_sts_masked = intr_sts & swrm->intr_mask; } while (intr_sts_masked);

• clk_disable_unprepare(swrm->hclk); return ret;

}

@@ -1017,6 +1032,15 @@ static int qcom_swrm_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *codec_dai; int ret, i;

• ret = pm_runtime_get_sync(ctrl->dev);
• if (ret < 0 && ret != -EACCES) {

• dev_err_ratelimited(ctrl->dev,
  

• 		    "pm_runtime_get_sync failed in %s, ret %d\n",
  

• 		    __func__, ret);
  

• pm_runtime_put_noidle(ctrl->dev);
  

• return ret;
  

• }
• sruntime = sdw_alloc_stream(dai->name); if (!sruntime) return -ENOMEM;

@@ -1044,6 +1068,9 @@ static void qcom_swrm_shutdown(struct snd_pcm_substream *substream,

sdw_release_stream(ctrl->sruntime[dai->id]); ctrl->sruntime[dai->id] = NULL;

• pm_runtime_mark_last_busy(ctrl->dev);
• pm_runtime_put_autosuspend(ctrl->dev);

}

static const struct snd_soc_dai_ops qcom_swrm_pdm_dai_ops = { @@ -1197,12 +1224,23 @@ static int qcom_swrm_get_port_config(struct qcom_swrm_ctrl *ctrl) static int swrm_reg_show(struct seq_file *s_file, void *data) { struct qcom_swrm_ctrl *swrm = s_file->private;

• int reg, reg_val;

• int reg, reg_val, ret;

• ret = pm_runtime_get_sync(swrm->dev);

• if (ret < 0 && ret != -EACCES) {

• dev_err_ratelimited(swrm->dev,
  

• 		    "pm_runtime_get_sync failed in %s, ret %d\n",
  

• 		    __func__, ret);
  

• pm_runtime_put_noidle(swrm->dev);
  

• }

  for (reg = 0; reg <= SWR_MSTR_MAX_REG_ADDR; reg += 4) { swrm->reg_read(swrm, reg, &reg_val); seq_printf(s_file, "0x%.3x: 0x%.2x\n", reg, reg_val); }

• pm_runtime_mark_last_busy(swrm->dev);

• pm_runtime_put_autosuspend(swrm->dev);

• return 0;

} @@ -1267,6 +1305,7 @@ static int qcom_swrm_probe(struct platform_device *pdev) ctrl->bus.ops = &qcom_swrm_ops; ctrl->bus.port_ops = &qcom_swrm_port_ops; ctrl->bus.compute_params = &qcom_swrm_compute_params;

• ctrl->bus.clk_stop_timeout = 300;

  ret = qcom_swrm_get_port_config(ctrl); if (ret)

@@ -1319,6 +1358,21 @@ static int qcom_swrm_probe(struct platform_device *pdev) (ctrl->version >> 24) & 0xff, (ctrl->version >> 16) & 0xff, ctrl->version & 0xffff);

• pm_runtime_set_autosuspend_delay(dev, 3000);
• pm_runtime_use_autosuspend(dev);
• pm_runtime_mark_last_busy(dev);
• pm_runtime_set_active(dev);
• pm_runtime_enable(dev);
• /* Clk stop is not supported on WSA Soundwire masters */
• if (ctrl->version <= 0x01030000) {

• ctrl->clock_stop_not_supported = true;
  

• } else {

• ctrl->reg_read(ctrl, SWRM_COMP_MASTER_ID, &val);
  

• if (val == MASTER_ID_WSA)
  

• 	ctrl->clock_stop_not_supported = true;
  

• }

#ifdef CONFIG_DEBUG_FS ctrl->debugfs = debugfs_create_dir("qualcomm-sdw", ctrl->bus.debugfs); debugfs_create_file("qualcomm-registers", 0400, ctrl->debugfs, ctrl, @@ -1345,6 +1399,105 @@ static int qcom_swrm_remove(struct platform_device *pdev) return 0; }

+static bool swrm_wait_for_frame_gen_enabled(struct qcom_swrm_ctrl *swrm) +{

• int retry = SWRM_LINK_STATUS_RETRY_CNT;
• int comp_sts;
• do {

• swrm->reg_read(swrm, SWRM_COMP_STATUS, &comp_sts);
  

• if (comp_sts & SWRM_FRM_GEN_ENABLED)
  

• 	return true;
  

• usleep_range(500, 510);
  

• } while (retry--);
• dev_err(swrm->dev, "%s: link status not %s\n", __func__,

• comp_sts && SWRM_FRM_GEN_ENABLED ? "connected" : "disconnected");
  

• return false;

+}

+static int swrm_runtime_resume(struct device *dev) +{

• struct qcom_swrm_ctrl *ctrl = dev_get_drvdata(dev);
• int ret;
• clk_prepare_enable(ctrl->hclk);
• if (ctrl->clock_stop_not_supported) {

• reinit_completion(&ctrl->enumeration);
  

• ctrl->reg_write(ctrl, SWRM_COMP_SW_RESET, 0x01);
  

• usleep_range(100, 105);
  

• qcom_swrm_init(ctrl);
  

• usleep_range(100, 105);
  

• if (!swrm_wait_for_frame_gen_enabled(ctrl))
  

• 	dev_err(ctrl->dev, "link failed to connect\n");
  

• /* wait for hw enumeration to complete */
  

• wait_for_completion_timeout(&ctrl->enumeration,
  

• 			    msecs_to_jiffies(TIMEOUT_MS));
  

• qcom_swrm_get_device_status(ctrl);
  

• sdw_handle_slave_status(&ctrl->bus, ctrl->status);
  

• } else {

• ctrl->reg_write(ctrl, SWRM_MCP_BUS_CTRL, SWRM_MCP_BUS_CLK_START);
  

• ctrl->reg_write(ctrl, SWRM_INTERRUPT_CLEAR,
  

• 	SWRM_INTERRUPT_STATUS_MASTER_CLASH_DET);
  

• ctrl->intr_mask |= SWRM_INTERRUPT_STATUS_MASTER_CLASH_DET;
  

• ctrl->reg_write(ctrl, SWRM_INTERRUPT_MASK_ADDR, ctrl->intr_mask);
  

• ctrl->reg_write(ctrl, SWRM_INTERRUPT_CPU_EN, ctrl->intr_mask);
  

• usleep_range(100, 105);
  

• if (!swrm_wait_for_frame_gen_enabled(ctrl))
  

• 	dev_err(ctrl->dev, "link failed to connect\n");
  

• ret = sdw_bus_exit_clk_stop(&ctrl->bus);
  

• if (ret < 0)
  

• 	dev_err(ctrl->dev, "bus failed to exit clock stop %d\n", ret);
  

• }
• return 0;

+}

+static int __maybe_unused swrm_runtime_suspend(struct device *dev) +{

• struct qcom_swrm_ctrl *ctrl = dev_get_drvdata(dev);
• int ret;
• if (!ctrl->clock_stop_not_supported) {

• /* Mask bus clash interrupt */
  

• ctrl->intr_mask &= ~SWRM_INTERRUPT_STATUS_MASTER_CLASH_DET;
  

• ctrl->reg_write(ctrl, SWRM_INTERRUPT_MASK_ADDR, ctrl->intr_mask);
  

• ctrl->reg_write(ctrl, SWRM_INTERRUPT_CPU_EN, ctrl->intr_mask);
  

• /* Prepare slaves for clock stop */
  

• ret = sdw_bus_prep_clk_stop(&ctrl->bus);
  

• if (ret < 0 && ret != -ENODATA) {
  

• 	dev_err(dev, "prepare clock stop failed %d", ret);
  

• 	return ret;
  

• }
  

• ret = sdw_bus_clk_stop(&ctrl->bus);
  

• if (ret < 0 && ret != -ENODATA) {
  

• 	dev_err(dev, "bus clock stop failed %d", ret);
  

• 	return ret;
  

• }
  

• }
• clk_disable_unprepare(ctrl->hclk);
• usleep_range(300, 305);
• return 0;

+}

+static const struct dev_pm_ops swrm_dev_pm_ops = {

• SET_RUNTIME_PM_OPS(swrm_runtime_suspend, swrm_runtime_resume, NULL)

+};

static const struct of_device_id qcom_swrm_of_match[] = { { .compatible = "qcom,soundwire-v1.3.0", .data = &swrm_v1_3_data }, { .compatible = "qcom,soundwire-v1.5.1", .data = &swrm_v1_5_data }, @@ -1359,6 +1512,7 @@ static struct platform_driver qcom_swrm_driver = { .driver = { .name = "qcom-soundwire", .of_match_table = qcom_swrm_of_match,

• .pm = &swrm_dev_pm_ops,
  

  }

}; module_platform_driver(qcom_swrm_driver);