soundwire: qcom: add debugfs entry for soundwire register dump

For debug purposes add an entry in debugfs to dump Qualcomm
SoundWire Controller registers.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210907105636.3171-1-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index 0ef79d6..a317bea 100644 (file)
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -7,6 +7,7 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/debugfs.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_device.h>
@@ -83,6 +84,7 @@
 #define SWRM_DP_PORT_HCTRL_BANK(n, m)  (0x1134 + 0x100 * (n - 1) + 0x40 * m)
 #define SWRM_DP_BLOCK_CTRL3_BANK(n, m) (0x1138 + 0x100 * (n - 1) + 0x40 * m)
 #define SWRM_DIN_DPn_PCM_PORT_CTRL(n)  (0x1054 + 0x100 * (n - 1))
+#define SWR_MSTR_MAX_REG_ADDR          (0x1740)
 
 #define SWRM_DP_PORT_CTRL_EN_CHAN_SHFT                         0x18
 #define SWRM_DP_PORT_CTRL_OFFSET2_SHFT                         0x10
@@ -127,6 +129,9 @@ struct qcom_swrm_ctrl {
        struct device *dev;
        struct regmap *regmap;
        void __iomem *mmio;
+#ifdef CONFIG_DEBUG_FS
+       struct dentry *debugfs;
+#endif
        struct completion broadcast;
        struct completion enumeration;
        struct work_struct slave_work;
@@ -1192,6 +1197,22 @@ static int qcom_swrm_get_port_config(struct qcom_swrm_ctrl *ctrl)
        return 0;
 }
 
+#ifdef CONFIG_DEBUG_FS
+static int swrm_reg_show(struct seq_file *s_file, void *data)
+{
+       struct qcom_swrm_ctrl *swrm = s_file->private;
+       int reg, reg_val;
+
+       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);
+       }
+
+       return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(swrm_reg);
+#endif
+
 static int qcom_swrm_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
@@ -1302,6 +1323,12 @@ static int qcom_swrm_probe(struct platform_device *pdev)
                 (ctrl->version >> 24) & 0xff, (ctrl->version >> 16) & 0xff,
                 ctrl->version & 0xffff);
 
+#ifdef CONFIG_DEBUG_FS
+       ctrl->debugfs = debugfs_create_dir("qualcomm-sdw", ctrl->bus.debugfs);
+       debugfs_create_file("qualcomm-registers", 0400, ctrl->debugfs, ctrl,
+                           &swrm_reg_fops);
+#endif
+
        return 0;
 
 err_master_add: