From: Christian A. Ehrhardt Date: Mon, 17 Feb 2025 10:54:39 +0000 (+0300) Subject: acpi: typec: ucsi: Introduce a ->poll_cci method X-Git-Tag: v6.12.19~47 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=012b98cdb54c7d47743ee7fc402fa23f2d90529a;p=thirdparty%2Fkernel%2Fstable.git acpi: typec: ucsi: Introduce a ->poll_cci method commit 976e7e9bdc7719a023a4ecccd2e3daec9ab20a40 upstream. For the ACPI backend of UCSI the UCSI "registers" are just a memory copy of the register values in an opregion. The ACPI implementation in the BIOS ensures that the opregion contents are synced to the embedded controller and it ensures that the registers (in particular CCI) are synced back to the opregion on notifications. While there is an ACPI call that syncs the actual registers to the opregion there is rarely a need to do this and on some ACPI implementations it actually breaks in various interesting ways. The only reason to force a sync from the embedded controller is to poll CCI while notifications are disabled. Only the ucsi core knows if this is the case and guessing based on the current command is suboptimal, i.e. leading to the following spurious assertion splat: WARNING: CPU: 3 PID: 76 at drivers/usb/typec/ucsi/ucsi.c:1388 ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi] CPU: 3 UID: 0 PID: 76 Comm: kworker/3:0 Not tainted 6.12.11-200.fc41.x86_64 #1 Hardware name: LENOVO 21D0/LNVNB161216, BIOS J6CN45WW 03/17/2023 Workqueue: events_long ucsi_init_work [typec_ucsi] RIP: 0010:ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi] Call Trace: ucsi_init_work+0x3c/0xac0 [typec_ucsi] process_one_work+0x179/0x330 worker_thread+0x252/0x390 kthread+0xd2/0x100 ret_from_fork+0x34/0x50 ret_from_fork_asm+0x1a/0x30 Thus introduce a ->poll_cci() method that works like ->read_cci() with an additional forced sync and document that this should be used when polling with notifications disabled. For all other backends that presumably don't have this issue use the same implementation for both methods. Fixes: fa48d7e81624 ("usb: typec: ucsi: Do not call ACPI _DSM method for UCSI read operations") Cc: stable Signed-off-by: Christian A. Ehrhardt Tested-by: Fedor Pchelkin Signed-off-by: Fedor Pchelkin Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20250217105442.113486-2-boddah8794@gmail.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 619bda11f2972..3f2bc13efa486 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -1330,7 +1330,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) mutex_lock(&ucsi->ppm_lock); - ret = ucsi->ops->read_cci(ucsi, &cci); + ret = ucsi->ops->poll_cci(ucsi, &cci); if (ret < 0) goto out; @@ -1348,7 +1348,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); do { - ret = ucsi->ops->read_cci(ucsi, &cci); + ret = ucsi->ops->poll_cci(ucsi, &cci); if (ret < 0) goto out; if (cci & UCSI_CCI_COMMAND_COMPLETE) @@ -1377,7 +1377,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) /* Give the PPM time to process a reset before reading CCI */ msleep(20); - ret = ucsi->ops->read_cci(ucsi, &cci); + ret = ucsi->ops->poll_cci(ucsi, &cci); if (ret) goto out; @@ -1913,8 +1913,8 @@ struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops) struct ucsi *ucsi; if (!ops || - !ops->read_version || !ops->read_cci || !ops->read_message_in || - !ops->sync_control || !ops->async_control) + !ops->read_version || !ops->read_cci || !ops->poll_cci || + !ops->read_message_in || !ops->sync_control || !ops->async_control) return ERR_PTR(-EINVAL); ucsi = kzalloc(sizeof(*ucsi), GFP_KERNEL); diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h index 1cf5aad4c23a9..a333006d3496a 100644 --- a/drivers/usb/typec/ucsi/ucsi.h +++ b/drivers/usb/typec/ucsi/ucsi.h @@ -60,6 +60,7 @@ struct dentry; * struct ucsi_operations - UCSI I/O operations * @read_version: Read implemented UCSI version * @read_cci: Read CCI register + * @poll_cci: Read CCI register while polling with notifications disabled * @read_message_in: Read message data from UCSI * @sync_control: Blocking control operation * @async_control: Non-blocking control operation @@ -74,6 +75,7 @@ struct dentry; struct ucsi_operations { int (*read_version)(struct ucsi *ucsi, u16 *version); int (*read_cci)(struct ucsi *ucsi, u32 *cci); + int (*poll_cci)(struct ucsi *ucsi, u32 *cci); int (*read_message_in)(struct ucsi *ucsi, void *val, size_t val_len); int (*sync_control)(struct ucsi *ucsi, u64 command); int (*async_control)(struct ucsi *ucsi, u64 command); diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c index accf15ff1306a..8de2961718cdd 100644 --- a/drivers/usb/typec/ucsi/ucsi_acpi.c +++ b/drivers/usb/typec/ucsi/ucsi_acpi.c @@ -59,19 +59,24 @@ static int ucsi_acpi_read_version(struct ucsi *ucsi, u16 *version) static int ucsi_acpi_read_cci(struct ucsi *ucsi, u32 *cci) { struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi); - int ret; - - if (UCSI_COMMAND(ua->cmd) == UCSI_PPM_RESET) { - ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ); - if (ret) - return ret; - } memcpy(cci, ua->base + UCSI_CCI, sizeof(*cci)); return 0; } +static int ucsi_acpi_poll_cci(struct ucsi *ucsi, u32 *cci) +{ + struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi); + int ret; + + ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ); + if (ret) + return ret; + + return ucsi_acpi_read_cci(ucsi, cci); +} + static int ucsi_acpi_read_message_in(struct ucsi *ucsi, void *val, size_t val_len) { struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi); @@ -94,6 +99,7 @@ static int ucsi_acpi_async_control(struct ucsi *ucsi, u64 command) static const struct ucsi_operations ucsi_acpi_ops = { .read_version = ucsi_acpi_read_version, .read_cci = ucsi_acpi_read_cci, + .poll_cci = ucsi_acpi_poll_cci, .read_message_in = ucsi_acpi_read_message_in, .sync_control = ucsi_sync_control_common, .async_control = ucsi_acpi_async_control @@ -145,6 +151,7 @@ static int ucsi_gram_sync_control(struct ucsi *ucsi, u64 command) static const struct ucsi_operations ucsi_gram_ops = { .read_version = ucsi_acpi_read_version, .read_cci = ucsi_acpi_read_cci, + .poll_cci = ucsi_acpi_poll_cci, .read_message_in = ucsi_gram_read_message_in, .sync_control = ucsi_gram_sync_control, .async_control = ucsi_acpi_async_control diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c index 740171f24ef9f..4b1668733a4be 100644 --- a/drivers/usb/typec/ucsi/ucsi_ccg.c +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c @@ -664,6 +664,7 @@ err_put: static const struct ucsi_operations ucsi_ccg_ops = { .read_version = ucsi_ccg_read_version, .read_cci = ucsi_ccg_read_cci, + .poll_cci = ucsi_ccg_read_cci, .read_message_in = ucsi_ccg_read_message_in, .sync_control = ucsi_ccg_sync_control, .async_control = ucsi_ccg_async_control, diff --git a/drivers/usb/typec/ucsi/ucsi_glink.c b/drivers/usb/typec/ucsi/ucsi_glink.c index 9b6cb76e63280..75c0e54c37fa0 100644 --- a/drivers/usb/typec/ucsi/ucsi_glink.c +++ b/drivers/usb/typec/ucsi/ucsi_glink.c @@ -201,6 +201,7 @@ static void pmic_glink_ucsi_connector_status(struct ucsi_connector *con) static const struct ucsi_operations pmic_glink_ucsi_ops = { .read_version = pmic_glink_ucsi_read_version, .read_cci = pmic_glink_ucsi_read_cci, + .poll_cci = pmic_glink_ucsi_read_cci, .read_message_in = pmic_glink_ucsi_read_message_in, .sync_control = ucsi_sync_control_common, .async_control = pmic_glink_ucsi_async_control, diff --git a/drivers/usb/typec/ucsi/ucsi_stm32g0.c b/drivers/usb/typec/ucsi/ucsi_stm32g0.c index 6923fad31d795..57ef7d83a4121 100644 --- a/drivers/usb/typec/ucsi/ucsi_stm32g0.c +++ b/drivers/usb/typec/ucsi/ucsi_stm32g0.c @@ -424,6 +424,7 @@ static irqreturn_t ucsi_stm32g0_irq_handler(int irq, void *data) static const struct ucsi_operations ucsi_stm32g0_ops = { .read_version = ucsi_stm32g0_read_version, .read_cci = ucsi_stm32g0_read_cci, + .poll_cci = ucsi_stm32g0_read_cci, .read_message_in = ucsi_stm32g0_read_message_in, .sync_control = ucsi_sync_control_common, .async_control = ucsi_stm32g0_async_control, diff --git a/drivers/usb/typec/ucsi/ucsi_yoga_c630.c b/drivers/usb/typec/ucsi/ucsi_yoga_c630.c index f3a5e24ea84d5..40e5da4fd2a45 100644 --- a/drivers/usb/typec/ucsi/ucsi_yoga_c630.c +++ b/drivers/usb/typec/ucsi/ucsi_yoga_c630.c @@ -74,6 +74,7 @@ static int yoga_c630_ucsi_async_control(struct ucsi *ucsi, u64 command) const struct ucsi_operations yoga_c630_ucsi_ops = { .read_version = yoga_c630_ucsi_read_version, .read_cci = yoga_c630_ucsi_read_cci, + .poll_cci = yoga_c630_ucsi_read_cci, .read_message_in = yoga_c630_ucsi_read_message_in, .sync_control = ucsi_sync_control_common, .async_control = yoga_c630_ucsi_async_control,