| Message ID | 20230512122838.243002-2-ckeepax@opensource.cirrus.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add cs42l43 PC focused SoundWire CODEC | expand |
> @@ -1711,6 +1739,9 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave) > struct device *dev = &slave->dev; > struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); > > + if (slave->prop.use_domain_irq && slave->irq) > + handle_nested_irq(slave->irq); > + I am a bit lost here, I can understand that alerts would be handled by a dedicated handler, but here the code continues and will call the existing interrupt_callback. Is this intentional? I wonder if there's a risk with two entities dealing with the same event and programming the same registers. Shouldn't there be some sort of 'either or' rule? > if (drv->ops && drv->ops->interrupt_callback) { > slave_intr.sdca_cascade = sdca_cascade; > slave_intr.control_port = clear; > diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c > index 1f43ee848eac8..fafbc284e82da 100644 > --- a/drivers/soundwire/bus_type.c > +++ b/drivers/soundwire/bus_type.c > @@ -122,6 +122,12 @@ static int sdw_drv_probe(struct device *dev) > if (drv->ops && drv->ops->read_prop) > drv->ops->read_prop(slave); > > + if (slave->prop.use_domain_irq) { > + slave->irq = irq_create_mapping(slave->bus->domain, slave->dev_num); > + if (!slave->irq) > + dev_warn(dev, "Failed to map IRQ\n"); > + } > + > /* init the sysfs as we have properties now */ > ret = sdw_slave_sysfs_init(slave); > if (ret < 0) > @@ -166,7 +172,13 @@ static int sdw_drv_remove(struct device *dev) > int ret = 0; > > mutex_lock(&slave->sdw_dev_lock); > + > slave->probed = false; > + > + if (slave->prop.use_domain_irq) > + irq_dispose_mapping(irq_find_mapping(slave->bus->domain, > + slave->dev_num)); > + > mutex_unlock(&slave->sdw_dev_lock); > > if (drv->remove) > diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h > index ef645de13ae93..c3ab5e5f9cfa4 100644 > --- a/include/linux/soundwire/sdw.h > +++ b/include/linux/soundwire/sdw.h > @@ -5,6 +5,8 @@ > #define __SOUNDWIRE_H > > #include <linux/bug.h> > +#include <linux/irq.h> > +#include <linux/irqdomain.h> > #include <linux/mod_devicetable.h> > #include <linux/bitfield.h> > > @@ -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. > + * @use_domain_irq: call actual IRQ handler on slave, as well as callback what callback, the interrupt_callback? That would mean the interrupt is handled twice? I am probably missing something here? > */ > 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 use_domain_irq; > };
On 5/12/23 11:02, Charles Keepax wrote: > On Fri, May 12, 2023 at 08:45:51AM -0500, Pierre-Louis Bossart wrote: >>> @@ -1711,6 +1739,9 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave) >>> struct device *dev = &slave->dev; >>> struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); >>> >>> + if (slave->prop.use_domain_irq && slave->irq) >>> + handle_nested_irq(slave->irq); >>> + >> >> I am a bit lost here, I can understand that alerts would be handled by a >> dedicated handler, but here the code continues and will call the >> existing interrupt_callback. >> >> Is this intentional? I wonder if there's a risk with two entities >> dealing with the same event and programming the same registers. >> Shouldn't there be some sort of 'either or' rule? >> > > I guess there is a risk of them "handling" the IRQ twice, > although it is hard to see why you would write the driver that > way. Also since they are sequencial the second would I guess > just see that no IRQs are pending. > > The intention for calling both is that it facilitates using > the same IRQ handler for I2C and SoundWire. At least on the > Cirrus devices there are a bunch of chip specific registers > that need treated exactly the same on I2C and SoundWire, but > then a couple of extra registers that need handled in the > SoundWire case. This way the handling of those can be kept > completely in the SoundWire part of the code and not ifdef-ed > into the main IRQ path. Sounds good to me, but it's worth adding a comment and improving the commit message with design intent/rules since it's a common part in drivers/soundwire/
On Fri, May 12, 2023 at 11:34:44AM -0500, Pierre-Louis Bossart wrote: > > > On 5/12/23 11:02, Charles Keepax wrote: > > On Fri, May 12, 2023 at 08:45:51AM -0500, Pierre-Louis Bossart wrote: > >>> @@ -1711,6 +1739,9 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave) > >>> struct device *dev = &slave->dev; > >>> struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); > >>> > >>> + if (slave->prop.use_domain_irq && slave->irq) > >>> + handle_nested_irq(slave->irq); > >>> + > >> > >> I am a bit lost here, I can understand that alerts would be handled by a > >> dedicated handler, but here the code continues and will call the > >> existing interrupt_callback. > >> > >> Is this intentional? I wonder if there's a risk with two entities > >> dealing with the same event and programming the same registers. > >> Shouldn't there be some sort of 'either or' rule? > >> > > > > I guess there is a risk of them "handling" the IRQ twice, > > although it is hard to see why you would write the driver that > > way. Also since they are sequencial the second would I guess > > just see that no IRQs are pending. > > > > The intention for calling both is that it facilitates using > > the same IRQ handler for I2C and SoundWire. At least on the > > Cirrus devices there are a bunch of chip specific registers > > that need treated exactly the same on I2C and SoundWire, but > > then a couple of extra registers that need handled in the > > SoundWire case. This way the handling of those can be kept > > completely in the SoundWire part of the code and not ifdef-ed > > into the main IRQ path. > > Sounds good to me, but it's worth adding a comment and improving the > commit message with design intent/rules since it's a common part in > drivers/soundwire/ Yeah no issues with updating the commit message to explain that in more detail. Thanks, Charles
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 1ea6a64f8c4a5..30cd03757aafe 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -3,6 +3,7 @@ #include <linux/acpi.h> #include <linux/delay.h> +#include <linux/irq.h> #include <linux/mod_devicetable.h> #include <linux/pm_runtime.h> #include <linux/soundwire/sdw_registers.h> @@ -25,6 +26,23 @@ static int sdw_get_id(struct sdw_bus *bus) return 0; } +static int sdw_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + struct sdw_bus *bus = h->host_data; + + irq_set_chip_data(virq, bus); + irq_set_chip(virq, &bus->irq_chip); + irq_set_nested_thread(virq, 1); + irq_set_noprobe(virq); + + return 0; +} + +static const struct irq_domain_ops sdw_domain_ops = { + .map = sdw_irq_map, +}; + /** * sdw_bus_master_add() - add a bus Master instance * @bus: bus instance @@ -142,6 +160,13 @@ int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent, bus->params.curr_bank = SDW_BANK0; bus->params.next_bank = SDW_BANK1; + bus->irq_chip.name = dev_name(bus->dev); + bus->domain = irq_domain_add_linear(NULL, SDW_MAX_DEVICES, &sdw_domain_ops, bus); + if (!bus->domain) { + dev_err(bus->dev, "Failed to add IRQ domain\n"); + return -EINVAL; + } + return 0; } EXPORT_SYMBOL(sdw_bus_master_add); @@ -178,6 +203,9 @@ static int sdw_delete_slave(struct device *dev, void *data) void sdw_bus_master_delete(struct sdw_bus *bus) { device_for_each_child(bus->dev, NULL, sdw_delete_slave); + + irq_domain_remove(bus->domain); + sdw_master_device_del(bus); sdw_bus_debugfs_exit(bus); @@ -1711,6 +1739,9 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave) struct device *dev = &slave->dev; struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); + if (slave->prop.use_domain_irq && slave->irq) + handle_nested_irq(slave->irq); + if (drv->ops && drv->ops->interrupt_callback) { slave_intr.sdca_cascade = sdca_cascade; slave_intr.control_port = clear; diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index 1f43ee848eac8..fafbc284e82da 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -122,6 +122,12 @@ static int sdw_drv_probe(struct device *dev) if (drv->ops && drv->ops->read_prop) drv->ops->read_prop(slave); + if (slave->prop.use_domain_irq) { + slave->irq = irq_create_mapping(slave->bus->domain, slave->dev_num); + if (!slave->irq) + dev_warn(dev, "Failed to map IRQ\n"); + } + /* init the sysfs as we have properties now */ ret = sdw_slave_sysfs_init(slave); if (ret < 0) @@ -166,7 +172,13 @@ static int sdw_drv_remove(struct device *dev) int ret = 0; mutex_lock(&slave->sdw_dev_lock); + slave->probed = false; + + if (slave->prop.use_domain_irq) + irq_dispose_mapping(irq_find_mapping(slave->bus->domain, + slave->dev_num)); + mutex_unlock(&slave->sdw_dev_lock); if (drv->remove) diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index ef645de13ae93..c3ab5e5f9cfa4 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -5,6 +5,8 @@ #define __SOUNDWIRE_H #include <linux/bug.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> #include <linux/mod_devicetable.h> #include <linux/bitfield.h> @@ -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. + * @use_domain_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 use_domain_irq; }; #define SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY BIT(0) @@ -640,6 +644,7 @@ struct sdw_slave_ops { * struct sdw_slave - SoundWire Slave * @id: MIPI device ID * @dev: Linux device + * @irq: IRQ number * @status: Status reported by the Slave * @bus: Bus handle * @prop: Slave properties @@ -669,6 +674,7 @@ struct sdw_slave_ops { struct sdw_slave { struct sdw_slave_id id; struct device dev; + int irq; enum sdw_slave_status status; struct sdw_bus *bus; struct sdw_slave_prop prop; @@ -883,6 +889,7 @@ struct sdw_master_ops { * is used to compute and program bus bandwidth, clock, frame shape, * transport and port parameters * @debugfs: Bus debugfs + * @domain: IRQ domain * @defer_msg: Defer message * @clk_stop_timeout: Clock stop timeout computed * @bank_switch_timeout: Bank switch timeout computed @@ -916,6 +923,8 @@ struct sdw_bus { #ifdef CONFIG_DEBUG_FS struct dentry *debugfs; #endif + struct irq_chip irq_chip; + struct irq_domain *domain; struct sdw_defer defer_msg; unsigned int clk_stop_timeout; u32 bank_switch_timeout;