It is rather inefficient to be constantly enabling/disabling the PM
runtime as we print out each individual register, switch to holding a PM
runtime reference across the whole register output.
Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/soundwire/debugfs.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c
index 49900cd207bc7..0718e9cda138a 100644
--- a/drivers/soundwire/debugfs.c
+++ b/drivers/soundwire/debugfs.c
@@ -4,6 +4,7 @@
#include <linux/device.h>
#include <linux/debugfs.h>
#include <linux/mod_devicetable.h>
+#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/soundwire/sdw.h>
#include <linux/soundwire/sdw_registers.h>
@@ -35,7 +36,7 @@ static ssize_t sdw_sprintf(struct sdw_slave *slave,
{
int value;
- value = sdw_read(slave, reg);
+ value = sdw_read_no_pm(slave, reg);
if (value < 0)
return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg);
@@ -55,6 +56,10 @@ static int sdw_slave_reg_show(struct seq_file *s_file, void *data)
if (!buf)
return -ENOMEM;
+ ret = pm_runtime_resume_and_get(&slave->dev);
+ if (ret < 0 && ret != -EACCES)
+ return ret;
+
ret = scnprintf(buf, RD_BUF, "Register Value\n");
/* DP0 non-banked registers */
@@ -112,6 +117,10 @@ static int sdw_slave_reg_show(struct seq_file *s_file, void *data)
}
seq_printf(s_file, "%s", buf);
+
+ pm_runtime_mark_last_busy(&slave->dev);
+ pm_runtime_put(&slave->dev);
+
kfree(buf);
return 0;
--
2.30.2
