On Thu, 19 Oct 2017 05:03:24 +0200, Vinod Koul wrote:
+static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i) +{
- struct sdw_slave *slave;
- list_for_each_entry(slave, &bus->slaves, node) {
if (slave->dev_num == i)return slave;- }
- return NULL;
Is this performed always in bus_lock, right? Better to document it.
+static int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id) +{
- if ((slave->id.unique_id != id.unique_id) ||
(slave->id.mfg_id != id.mfg_id) ||(slave->id.part_id != id.part_id) ||(slave->id.class_id != id.class_id))
Align indentations.
+static int sdw_get_device_num(struct sdw_slave *slave) +{
- bool assigned = false;
- int i;
- mutex_lock(&slave->bus->bus_lock);
- for (i = 1; i <= SDW_MAX_DEVICES; i++) {
if (slave->bus->assigned[i] == true)continue;slave->bus->assigned[i] = true;assigned = true;/** Do not update dev_num in Slave data structure here,* Update once program dev_num is successful*/break;
With the bitmap, it's easier, you can use find_next_zero_bit() :)
+static int sdw_program_device_num(struct sdw_bus *bus) +{
- u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
- unsigned long long addr;
Use u64.
- struct sdw_slave *slave;
- struct sdw_slave_id id;
- struct sdw_msg msg;
- bool found = false;
- int ret;
- /* No Slave, so use raw xfer api */
- sdw_fill_msg(&msg, SDW_SCP_DEVID_0, SDW_NUM_DEV_ID_REGISTERS,
0, SDW_MSG_FLAG_READ, buf);- do {
ret = sdw_transfer(bus, NULL, &msg);if (ret == -ENODATA)break;if (ret < 0) {dev_err(bus->dev, "DEVID read fail:%d\n", ret);break;
So here we break, and the function returns zero. Is this the expected behavior?
}/** Construct the addr and extract. Cast the higher shift* bits to avoid truncation due to size limit.*/addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |(buf[2] << 24) | ((unsigned long long)buf[1] << 32) |((unsigned long long)buf[0] << 40);sdw_extract_slave_id(bus, addr, &id);/* Now compare with entries */list_for_each_entry(slave, &bus->slaves, node) {
Isn't this function protected under bus_lock...?
if (sdw_compare_devid(slave, id) == 0) {found = true;/** Assign a new dev_num to this Slave and* not mark it present. It will be marked* present after it reports ATTACHED on new* dev_num*/ret = sdw_assign_device_num(slave);if (ret) {dev_err(slave->bus->dev,"Assign dev_num failed:%d",ret);return ret;}break;}}if (found == false) {/* TODO: Park this device in Group 13 */dev_err(bus->dev, "Slave Entry not found");
No break here? Otherwise...
}- } while (ret == 0);
... the outer loop may go endlessly. This condition doesn't look effective.
- return 0;
... and here returns no error?
thanks,
Takashi