6.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sibi Sankar <quic_sibis@xxxxxxxxxxx> commit 899f44531fe6cac4b024710fec647ecc127724b8 upstream. Introduce GENPD_FLAG_DEV_NAME_FW flag which instructs genpd to generate an unique device name using ida. It is aimed to be used by genpd providers which derive their names directly from FW making them susceptible to debugfs node creation failures. Reported-by: Johan Hovold <johan+linaro@xxxxxxxxxx> Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@xxxxxxxxxxxxxxxxxxxx/ Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains") Suggested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Message-ID: <20241030125512.2884761-5-quic_sibis@xxxxxxxxxxx> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pmdomain/core.c | 49 +++++++++++++++++++++++++++++++--------------- include/linux/pm_domain.h | 6 +++++ 2 files changed, 40 insertions(+), 15 deletions(-) --- a/drivers/pmdomain/core.c +++ b/drivers/pmdomain/core.c @@ -7,6 +7,7 @@ #define pr_fmt(fmt) "PM: " fmt #include <linux/delay.h> +#include <linux/idr.h> #include <linux/kernel.h> #include <linux/io.h> #include <linux/platform_device.h> @@ -23,6 +24,9 @@ #include <linux/cpu.h> #include <linux/debugfs.h> +/* Provides a unique ID for each genpd device */ +static DEFINE_IDA(genpd_ida); + #define GENPD_RETRY_MAX_MS 250 /* Approximate */ #define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \ @@ -129,6 +133,7 @@ static const struct genpd_lock_ops genpd #define genpd_is_cpu_domain(genpd) (genpd->flags & GENPD_FLAG_CPU_DOMAIN) #define genpd_is_rpm_always_on(genpd) (genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON) #define genpd_is_opp_table_fw(genpd) (genpd->flags & GENPD_FLAG_OPP_TABLE_FW) +#define genpd_is_dev_name_fw(genpd) (genpd->flags & GENPD_FLAG_DEV_NAME_FW) static inline bool irq_safe_dev_in_sleep_domain(struct device *dev, const struct generic_pm_domain *genpd) @@ -147,7 +152,7 @@ static inline bool irq_safe_dev_in_sleep if (ret) dev_warn_once(dev, "PM domain %s will not be powered off\n", - genpd->name); + dev_name(&genpd->dev)); return ret; } @@ -232,7 +237,7 @@ static void genpd_debug_remove(struct ge if (!genpd_debugfs_dir) return; - debugfs_lookup_and_remove(genpd->name, genpd_debugfs_dir); + debugfs_lookup_and_remove(dev_name(&genpd->dev), genpd_debugfs_dir); } static void genpd_update_accounting(struct generic_pm_domain *genpd) @@ -689,7 +694,7 @@ static int _genpd_power_on(struct generi genpd->states[state_idx].power_on_latency_ns = elapsed_ns; genpd->gd->max_off_time_changed = true; pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n", - genpd->name, "on", elapsed_ns); + dev_name(&genpd->dev), "on", elapsed_ns); out: raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL); @@ -740,7 +745,7 @@ static int _genpd_power_off(struct gener genpd->states[state_idx].power_off_latency_ns = elapsed_ns; genpd->gd->max_off_time_changed = true; pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n", - genpd->name, "off", elapsed_ns); + dev_name(&genpd->dev), "off", elapsed_ns); out: raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF, @@ -1898,7 +1903,7 @@ int dev_pm_genpd_add_notifier(struct dev if (ret) { dev_warn(dev, "failed to add notifier for PM domain %s\n", - genpd->name); + dev_name(&genpd->dev)); return ret; } @@ -1945,7 +1950,7 @@ int dev_pm_genpd_remove_notifier(struct if (ret) { dev_warn(dev, "failed to remove notifier for PM domain %s\n", - genpd->name); + dev_name(&genpd->dev)); return ret; } @@ -1971,7 +1976,7 @@ static int genpd_add_subdomain(struct ge */ if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) { WARN(1, "Parent %s of subdomain %s must be IRQ safe\n", - genpd->name, subdomain->name); + dev_name(&genpd->dev), subdomain->name); return -EINVAL; } @@ -2046,7 +2051,7 @@ int pm_genpd_remove_subdomain(struct gen if (!list_empty(&subdomain->parent_links) || subdomain->device_count) { pr_warn("%s: unable to remove subdomain %s\n", - genpd->name, subdomain->name); + dev_name(&genpd->dev), subdomain->name); ret = -EBUSY; goto out; } @@ -2180,6 +2185,7 @@ int pm_genpd_init(struct generic_pm_doma genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON; genpd->device_count = 0; genpd->provider = NULL; + genpd->device_id = -ENXIO; genpd->has_provider = false; genpd->accounting_time = ktime_get_mono_fast_ns(); genpd->domain.ops.runtime_suspend = genpd_runtime_suspend; @@ -2220,7 +2226,18 @@ int pm_genpd_init(struct generic_pm_doma return ret; device_initialize(&genpd->dev); - dev_set_name(&genpd->dev, "%s", genpd->name); + + if (!genpd_is_dev_name_fw(genpd)) { + dev_set_name(&genpd->dev, "%s", genpd->name); + } else { + ret = ida_alloc(&genpd_ida, GFP_KERNEL); + if (ret < 0) { + put_device(&genpd->dev); + return ret; + } + genpd->device_id = ret; + dev_set_name(&genpd->dev, "%s_%u", genpd->name, genpd->device_id); + } mutex_lock(&gpd_list_lock); list_add(&genpd->gpd_list_node, &gpd_list); @@ -2242,13 +2259,13 @@ static int genpd_remove(struct generic_p if (genpd->has_provider) { genpd_unlock(genpd); - pr_err("Provider present, unable to remove %s\n", genpd->name); + pr_err("Provider present, unable to remove %s\n", dev_name(&genpd->dev)); return -EBUSY; } if (!list_empty(&genpd->parent_links) || genpd->device_count) { genpd_unlock(genpd); - pr_err("%s: unable to remove %s\n", __func__, genpd->name); + pr_err("%s: unable to remove %s\n", __func__, dev_name(&genpd->dev)); return -EBUSY; } @@ -2262,9 +2279,11 @@ static int genpd_remove(struct generic_p genpd_unlock(genpd); genpd_debug_remove(genpd); cancel_work_sync(&genpd->power_off_work); + if (genpd->device_id != -ENXIO) + ida_free(&genpd_ida, genpd->device_id); genpd_free_data(genpd); - pr_debug("%s: removed %s\n", __func__, genpd->name); + pr_debug("%s: removed %s\n", __func__, dev_name(&genpd->dev)); return 0; } @@ -3226,12 +3245,12 @@ static int genpd_summary_one(struct seq_ else snprintf(state, sizeof(state), "%s", status_lookup[genpd->status]); - seq_printf(s, "%-30s %-30s %u", genpd->name, state, genpd->performance_state); + seq_printf(s, "%-30s %-30s %u", dev_name(&genpd->dev), state, genpd->performance_state); /* * Modifications on the list require holding locks on both * parent and child, so we are safe. - * Also genpd->name is immutable. + * Also the device name is immutable. */ list_for_each_entry(link, &genpd->parent_links, parent_node) { if (list_is_first(&link->parent_node, &genpd->parent_links)) @@ -3456,7 +3475,7 @@ static void genpd_debug_add(struct gener if (!genpd_debugfs_dir) return; - d = debugfs_create_dir(genpd->name, genpd_debugfs_dir); + d = debugfs_create_dir(dev_name(&genpd->dev), genpd_debugfs_dir); debugfs_create_file("current_state", 0444, d, genpd, &status_fops); --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -92,6 +92,10 @@ struct dev_pm_domain_list { * GENPD_FLAG_OPP_TABLE_FW: The genpd provider supports performance states, * but its corresponding OPP tables are not * described in DT, but are given directly by FW. + * + * GENPD_FLAG_DEV_NAME_FW: Instructs genpd to generate an unique device name + * using ida. It is used by genpd providers which + * get their genpd-names directly from FW. */ #define GENPD_FLAG_PM_CLK (1U << 0) #define GENPD_FLAG_IRQ_SAFE (1U << 1) @@ -101,6 +105,7 @@ struct dev_pm_domain_list { #define GENPD_FLAG_RPM_ALWAYS_ON (1U << 5) #define GENPD_FLAG_MIN_RESIDENCY (1U << 6) #define GENPD_FLAG_OPP_TABLE_FW (1U << 7) +#define GENPD_FLAG_DEV_NAME_FW (1U << 8) enum gpd_status { GENPD_STATE_ON = 0, /* PM domain is on */ @@ -163,6 +168,7 @@ struct generic_pm_domain { atomic_t sd_count; /* Number of subdomains with power "on" */ enum gpd_status status; /* Current state of the domain */ unsigned int device_count; /* Number of devices */ + unsigned int device_id; /* unique device id */ unsigned int suspended_count; /* System suspend device counter */ unsigned int prepared_count; /* Suspend counter of prepared devices */ unsigned int performance_state; /* Aggregated max performance state */
