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
