On 08/19/2016 06:22 PM, Sudeep Holla wrote:

On 18/08/16 11:10, Neil Armstrong wrote:

quoted

In order to support legacy SCP functions from kernel-wide driver, add legacy
functions using the legacy command enums and calling legacy_scpi_send_message.

Signed-off-by: Neil Armstrong <redacted>
---
 drivers/firmware/arm_scpi.c | 118 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 118 insertions(+)

diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index 50b1297..bb9965f 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c

@@ -578,6 +578,8 @@ scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
     return ret;
 }

+/* scpi_clk_get_range not available for legacy */
+
 static unsigned long scpi_clk_get_val(u16 clk_id)
 {
     int ret;

@@ -589,6 +591,18 @@ static unsigned long scpi_clk_get_val(u16 clk_id)
     return ret ? ret : le32_to_cpu(clk.rate);
 }

+static unsigned long legacy_scpi_clk_get_val(u16 clk_id)
+{
+    int ret;
+    struct clk_get_value clk;
+    __le16 le_clk_id = cpu_to_le16(clk_id);
+
+    ret = legacy_scpi_send_message(LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
+                       &le_clk_id, sizeof(le_clk_id),
+                       &clk, sizeof(clk));
+    return ret ? ret : le32_to_cpu(clk.rate);
+}
+
 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
 {
     int stat;

@@ -601,6 +615,19 @@ static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
                  &stat, sizeof(stat));
 }

+static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
+{
+    int stat;
+    struct legacy_clk_set_value clk = {
+        .id = cpu_to_le16(clk_id),
+        .rate = cpu_to_le32(rate)
+    };
+
+    return legacy_scpi_send_message(LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
+                    &clk, sizeof(clk),
+                    &stat, sizeof(stat));

Except this one which has a different structure format, why do we need
to define legacy versions of other functions ? Can't we play with
function pointer or have a boolean in drvinfo structure and use then in
the existing functions as I had shown in one of the earlier emails.

The main problem is that the command indexes deviates starting at
SCPI_CMD_SET_CSS_PWR_STATE, I'll be pleased to know how to implement it.

Should I add a test :
if (scpi_drvinfo->is_legacy)
	legacy_scpi_send_message(...)
else
	scpi_send_message(...)

In each function ?

My strategy was to leave the "final" function untouched ans provide
alternatives to legacy.
I can add this "is_legacy" if/else instead of ops structures.

Please tell me how you'll implement this, so I'll adapt the merge.

Neil