On 1/20/23 03:59, Charles Keepax wrote:
On Thu, Jan 19, 2023 at 11:12:04AM -0600, Pierre-Louis Bossart wrote:
No objection on this addition, just a couple of comments to improve it:
EXPORT_SYMBOL(sdw_bus_master_add); @@ -158,6 +183,8 @@ static int sdw_delete_slave(struct device *dev, void *data) mutex_lock(&bus->bus_lock);
if (slave->dev_num) { /* clear dev_num if assigned */
irq_dispose_mapping(irq_find_mapping(bus->domain, slave->dev_num));
could this be done conditionally. e.g.
if (slave->prop.irq) irq_dispose_mapping(irq_find_mapping(bus->domain, slave->dev_num));
slave->irq = irq_create_mapping(bus->domain, dev_num);
if (!slave->irq) {
dev_err(bus->dev, "Failed to map IRQ\n");
return -EINVAL;
}
...and here....
if (slave->prop.irq) { slave->irq = irq_create_mapping(bus->domain, dev_num); if (!slave->irq) { dev_err(bus->dev, "Failed to map IRQ\n"); return -EINVAL; } }
Yeah I am happy to make those conditional, I guess it is cleaner to not map IRQs if they wont be used.
ok
@@ -369,6 +371,7 @@ struct sdw_dpn_prop {
- @clock_reg_supported: the Peripheral implements the clock base and scale
- registers introduced with the SoundWire 1.2 specification. SDCA devices
- do not need to set this boolean property as the registers are required.
*/
- @irq: call actual IRQ handler on slave, as well as callback
struct sdw_slave_prop { u32 mipi_revision; @@ -393,6 +396,7 @@ struct sdw_slave_prop { u8 scp_int1_mask; u32 quirks; bool clock_reg_supported;
- bool irq;
this can be confused with the 'wake_capable' property.
maybe 'out_of_band_irq' ?
Yes I struggle on the name a bit and then just gave up and went with plain "irq", hard to know what to call it. Not sure out_of_band is quite right since it not really out of band, handle_nested_irq pretty much basically boils down to a function call really. Maybe something like "map_irq", or "use_domain_irq"?
Naming is hard. I use 'in-band wake' for SoundWire-based notifications, so I used 'out-of-band' for non-SoundWire stuff.
use_domain_irq sounds goods to me, it's different enough that confusions are not possible.
There should be an explanation and something checking that both are not used concurrently.
I will try to expand the explanation a litte, but I dont see any reason to block calling both handlers, no ill effects would come for a driver having both and it is useful if any soundwire specific steps are needed that arn't on other control buses.
I think it's problematic if the peripheral tries to wake-up the manager from clock-stop with both an in-band wake (i.e. drive the data line high) and a separate GPIO-based interrupt. It's asking for trouble IMHO. We spent hours in the MIPI team to make sure there were no races between the manager-initiated restarts and peripheral-initiated restarts, adding a 3rd mechanism in the mix gives me a migraine already.