Re: [PATCH v3 1/8] scpi: Add cmd indirection table to prepare for legacy commands

From: Sudeep Holla
Date: Mon Sep 19 2016 - 10:42:01 EST


Hi Neil,

On 07/09/16 16:34, Neil Armstrong wrote:
Add indirection table to permit multiple command values for legacy support.


I wrote the most of the patch and you changed the author too ;)

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/firmware/arm_scpi.c | 145 ++++++++++++++++++++++++++++++++++++++------
1 file changed, 127 insertions(+), 18 deletions(-)

diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
index 4388937..9a87687 100644
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c

[..]

@@ -161,6 +194,7 @@ struct scpi_drvinfo {
u32 protocol_version;
u32 firmware_version;
int num_chans;
+ int *scpi_cmds;
atomic_t next_chan;
struct scpi_ops *scpi_ops;
struct scpi_chan *channels;
@@ -390,6 +424,19 @@ static u32 scpi_get_version(void)
return scpi_info->protocol_version;
}

+static inline int check_cmd(unsigned int offset)
+{
+ if (offset >= CMD_MAX_COUNT ||

If we call scpi_send_message internally(as it's static) why is this
check needed ?


+ !scpi_info ||
+ !scpi_info->scpi_cmds)

Will be even reach to this point if above is true ?

+ return -EINVAL;
+
+ if (scpi_info->scpi_cmds[offset] < 0)
+ return -EOPNOTSUPP;

IMO just above couple of lines in the beginning of scpi_send_message
will suffice. You can just add this to my original patch.

static int
scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
{
@@ -397,8 +444,13 @@ scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
struct clk_get_info clk;
__le16 le_clk_id = cpu_to_le16(clk_id);

- ret = scpi_send_message(SCPI_CMD_GET_CLOCK_INFO, &le_clk_id,
- sizeof(le_clk_id), &clk, sizeof(clk));
+ ret = check_cmd(CMD_GET_CLOCK_INFO);
+ if (ret)
+ return ret;
+

It's totally unnecessary to add check in each and every function calling
scpi_send_message, why not add it to scpi_send_message instead.

--
Regards,
Sudeep