On 09/20/2016 06:50 AM, Mika Westerberg wrote:
On Tue, Sep 20, 2016 at 06:37:23AM -0700, Guenter Roeck wrote:
+ for (i = 0; i < tbl->entries; i++) {
+ const struct acpi_generic_address *gas;
+ struct wdat_instruction *instr;
+ struct list_head *instructions;
+ unsigned int action;
+ struct resource r;
+ int j;
+
+ action = entries[i].action;
+ if (action >= MAX_WDAT_ACTIONS) {
+ dev_dbg(&pdev->dev, "Skipping unknown action: %u\n",
+ action);
+ continue;
+ }
+
+ instr = devm_kzalloc(&pdev->dev, sizeof(*instr), GFP_KERNEL);
+ if (!instr)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&instr->node);
+ instr->entry = entries[i];
+
+ gas = &entries[i].register_region;
+
+ memset(&r, 0, sizeof(r));
+ r.start = gas->address;
+ r.end = r.start + gas->access_width;
+ if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
+ r.flags = IORESOURCE_MEM;
+ } else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
+ r.flags = IORESOURCE_IO;
+ } else {
+ dev_dbg(&pdev->dev, "Unsupported address space: %d\n",
+ gas->space_id);
+ continue;
+ }
+
+ /* Find the matching resource */
+ for (j = 0; j < pdev->num_resources; j++) {
+ res = &pdev->resource[j];
+ if (resource_contains(res, &r)) {
+ instr->reg = regs[j] + r.start - res->start;
+ break;
+ }
+ }
+
+ if (!instr->reg) {
+ dev_err(&pdev->dev, "I/O resource not found\n");
+ return -EINVAL;
+ }
+
I must be missing something here. What is happening with instr ?
Instr contains the actual instruction from WDAT table. There can be
many.
+ instructions = wdat->instructions[action];
This will be NULL first time so...
+ if (!instructions) {
+ instructions = devm_kzalloc(&pdev->dev,
+ sizeof(*instructions), GFP_KERNEL);
+ if (!instructions)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(instructions);
+ wdat->instructions[action] = instructions;
... and I don't really see how wdat->instructions[action] contains anything but
a zero filled array. Confused :-(.
...we allocate entry for that here. Next time it will not be NULL for
that action.
+ }
+
+ list_add_tail(&instr->node, instructions);
Then we append each instr to the list for this action.
Hope this clarifies :)
Yes, I somehow didn't see that last line. Too early in the morning,
not enough coffee.
Thanks,
Guenter
