Re: [PATCH net-next] net: dsa: lan9303: Introduce lan9303_read_wait

[Egil Hjelmeland]

Hi Vivien.

Den 12. des. 2017 19:08, skrev Vivien Didelot:
Hi Egil,
Egil Hjelmeland <pri...@egil-hjelmeland.no> writes:

Simplify lan9303_indirect_phy_wait_for_completion()
and lan9303_switch_wait_for_completion() by using a new function
lan9303_read_wait()

Signed-off-by: Egil Hjelmeland <pri...@egil-hjelmeland.no>
---
  drivers/net/dsa/lan9303-core.c | 59 +++++++++++++++++++-----------------------
  1 file changed, 27 insertions(+), 32 deletions(-)

diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
index c1b004fa64d9..96ccce0939d3 100644
--- a/drivers/net/dsa/lan9303-core.c
+++ b/drivers/net/dsa/lan9303-core.c
@@ -249,6 +249,29 @@ static int lan9303_read(struct regmap *regmap, unsigned 
int offset, u32 *reg)
        return -EIO;
  }
  
+/* Wait a while until mask & reg == value. Otherwise return timeout. */
+static int lan9303_read_wait(struct lan9303 *chip, int offset, int mask,
+                            char value)
+{
+       int i;
+
+       for (i = 0; i < 25; i++) {
+               u32 reg;
+               int ret;
+
+               ret = lan9303_read(chip->regmap, offset, &reg);
+               if (ret) {
+                       dev_err(chip->dev, "%s failed to read offset %d: %d\n",
+                               __func__, offset, ret);
+                       return ret;
+               }
+               if ((reg & mask) == value)
+                       return 0;

That is weird to mix int, u32 and char for mask checking. I suggest you
to use the u32 type as well for both mask and value.


Good catch. Will fix that. Same with lan9303_csr_reg_wait() then.


Looking at how lan9303_read_wait is called, the value argument doesn't
seem necessary. You can directly return 0 if (!(reg & mask)).


The idea was to make in more general usable, in case one need to wait 
for a bit to be set. But I don't have any example from the datasheet 
that needs it, so I could take "value" away.

+               usleep_range(1000, 2000);
+       }
+       return -ETIMEDOUT;

A newline before the return statment would be appreciated.

Ok.

+}
+
  static int lan9303_virt_phy_reg_read(struct lan9303 *chip, int regnum)
  {
        int ret;
@@ -274,22 +297,8 @@ static int lan9303_virt_phy_reg_write(struct lan9303 
*chip, int regnum, u16 val)
  
  static int lan9303_indirect_phy_wait_for_completion(struct lan9303 *chip)
  {
-       int ret, i;
-       u32 reg;
-
-       for (i = 0; i < 25; i++) {
-               ret = lan9303_read(chip->regmap, LAN9303_PMI_ACCESS, &reg);
-               if (ret) {
-                       dev_err(chip->dev,
-                               "Failed to read pmi access status: %d\n", ret);
-                       return ret;
-               }
-               if (!(reg & LAN9303_PMI_ACCESS_MII_BUSY))
-                       return 0;
-               usleep_range(1000, 2000);
-       }
-
-       return -EIO;
+       return lan9303_read_wait(chip, LAN9303_PMI_ACCESS,
+                                LAN9303_PMI_ACCESS_MII_BUSY, 0);
  }
  
  static int lan9303_indirect_phy_read(struct lan9303 *chip, int addr, int regnum)
@@ -366,22 +375,8 @@ EXPORT_SYMBOL_GPL(lan9303_indirect_phy_ops);
  
  static int lan9303_switch_wait_for_completion(struct lan9303 *chip)
  {
-       int ret, i;
-       u32 reg;
-
-       for (i = 0; i < 25; i++) {
-               ret = lan9303_read(chip->regmap, LAN9303_SWITCH_CSR_CMD, &reg);
-               if (ret) {
-                       dev_err(chip->dev,
-                               "Failed to read csr command status: %d\n", ret);
-                       return ret;
-               }
-               if (!(reg & LAN9303_SWITCH_CSR_CMD_BUSY))
-                       return 0;
-               usleep_range(1000, 2000);
-       }
-
-       return -EIO;
+       return lan9303_read_wait(chip, LAN9303_SWITCH_CSR_CMD,
+                                LAN9303_SWITCH_CSR_CMD_BUSY, 0);
  }
  
  static int lan9303_write_switch_reg(struct lan9303 *chip, u16 regnum, u32 val)


Thanks,

         Vivien


Thanks, Egil