[PATCH v2] media: staging/ipu7: use guard(mutex) in ipu7-buttress.c

From: Laurian Iacob

Date: Thu Nov 05 2026 - 03:16:19 EST


Use scope-based guard(mutex) from linux/cleanup.h across
ipu7-buttress.c to simplify error handling, remove redundant goto
unlock labels, and ensure consistent mutex locking across all helper
functions.

Signed-off-by: Laurian Iacob <laurian.iacob@xxxxxxxxx>
---
Changes in v2:
- Restore the 'try:' label in ipu_buttress_ipc_send_msg() (Dan Carpenter)
- Remove leftover mutex_unlock() in ipu_buttress_ipc_send_msg() and dead
'ret = 0' in ipu_buttress_authenticate() (Dan Carpenter)
- Convert remaining mutexes in ipu7-buttress.c to guard(mutex)

drivers/staging/media/ipu7/ipu7-buttress.c | 75 +++++++++-------------
1 file changed, 29 insertions(+), 46 deletions(-)

diff --git a/drivers/staging/media/ipu7/ipu7-buttress.c b/drivers/staging/media/ipu7/ipu7-buttress.c
index 40c6c8473357..e79bdb742210 100644
--- a/drivers/staging/media/ipu7/ipu7-buttress.c
+++ b/drivers/staging/media/ipu7/ipu7-buttress.c
@@ -6,6 +6,7 @@
#include <asm/cpu_device_id.h>
#include <linux/bitfield.h>
#include <linux/bits.h>
+#include <linux/cleanup.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
@@ -76,7 +77,7 @@ int ipu_buttress_ipc_reset(struct ipu7_device *isp,
return 0;
}

- mutex_lock(&b->ipc_mutex);
+ guard(mutex)(&b->ipc_mutex);

/* Clear-by-1 CSR (all bits), corresponding internal states. */
val = readl(isp->base + ipc->csr_in);
@@ -155,7 +156,6 @@ int ipu_buttress_ipc_reset(struct ipu7_device *isp,
"RST_PHASE2 retry csr_in = %x\n", val);
break;
}
- mutex_unlock(&b->ipc_mutex);
return 0;
case QUERY:
/*
@@ -173,7 +173,6 @@ int ipu_buttress_ipc_reset(struct ipu7_device *isp,
}
} while (retries--);

- mutex_unlock(&b->ipc_mutex);
dev_err(dev, "Timed out while waiting for CSE\n");

return -ETIMEDOUT;
@@ -229,12 +228,12 @@ static int ipu_buttress_ipc_send_msg(struct ipu7_device *isp,
u32 val;
int ret;

- mutex_lock(&b->ipc_mutex);
+ guard(mutex)(&b->ipc_mutex);

ret = ipu_buttress_ipc_validity_open(isp, ipc);
if (ret) {
dev_err(dev, "IPC validity open failed\n");
- goto out;
+ return ret;
}

tx_timeout_jiffies = msecs_to_jiffies(BUTTRESS_IPC_TX_TIMEOUT_MS);
@@ -296,7 +295,6 @@ static int ipu_buttress_ipc_send_msg(struct ipu7_device *isp,

out:
ipu_buttress_ipc_validity_close(isp, ipc);
- mutex_unlock(&b->ipc_mutex);

return ret;
}
@@ -527,13 +525,13 @@ static int ipu7_buttress_powerup(struct device *dev,
if (!ctrl)
return 0;

- mutex_lock(&isp->buttress.power_mutex);
+ guard(mutex)(&isp->buttress.power_mutex);

exp_sts = ctrl->pwr_sts_on << ctrl->pwr_sts_shift;
if (ctrl->subsys_id == IPU_IS) {
ret = isys_d2d_power(dev, true);
if (ret)
- goto out_power;
+ return ret;
isys_nde_control(dev, true);
}

@@ -560,7 +558,7 @@ static int ipu7_buttress_powerup(struct device *dev,
if (ret) {
dev_err(dev, "%s power up timeout with status: 0x%x\n",
ctrl->subsys_id == IPU_IS ? "IS" : "PS", val);
- goto out_power;
+ return ret;
}

dev_dbg(dev, "%s power up successfully. status: 0x%x\n",
@@ -571,10 +569,7 @@ static int ipu7_buttress_powerup(struct device *dev,
val &= ~ctrl->ovrd_clk;
writel(val, isp->base + BUTTRESS_REG_SLEEP_LEVEL_CFG);

-out_power:
- mutex_unlock(&isp->buttress.power_mutex);
-
- return ret;
+ return 0;
}

static int ipu7_buttress_powerdown(struct device *dev,
@@ -587,7 +582,7 @@ static int ipu7_buttress_powerdown(struct device *dev,
if (!ctrl)
return 0;

- mutex_lock(&isp->buttress.power_mutex);
+ guard(mutex)(&isp->buttress.power_mutex);

exp_sts = ctrl->pwr_sts_off << ctrl->pwr_sts_shift;
val = 0x8U << ctrl->ratio_shift;
@@ -601,20 +596,18 @@ static int ipu7_buttress_powerdown(struct device *dev,
if (ret) {
dev_err(dev, "%s power down timeout with status: 0x%x\n",
ctrl->subsys_id == IPU_IS ? "IS" : "PS", val);
- goto out_power;
+ return ret;
}

dev_dbg(dev, "%s power down successfully. status: 0x%x\n",
ctrl->subsys_id == IPU_IS ? "IS" : "PS", val);
-out_power:
- if (ctrl->subsys_id == IPU_IS && !ret) {
+
+ if (ctrl->subsys_id == IPU_IS) {
isys_d2d_power(dev, false);
isys_nde_control(dev, false);
}

- mutex_unlock(&isp->buttress.power_mutex);
-
- return ret;
+ return 0;
}

static int ipu8_buttress_powerup(struct device *dev,
@@ -628,12 +621,12 @@ static int ipu8_buttress_powerup(struct device *dev,
if (!ctrl)
return 0;

- mutex_lock(&isp->buttress.power_mutex);
+ guard(mutex)(&isp->buttress.power_mutex);
exp_sts = ctrl->pwr_sts_on << ctrl->pwr_sts_shift;
if (ctrl->subsys_id == IPU_IS) {
ret = isys_d2d_power(dev, true);
if (ret)
- goto out_power;
+ return ret;
isys_nde_control(dev, true);
}

@@ -658,15 +651,13 @@ static int ipu8_buttress_powerup(struct device *dev,
if (ret) {
dev_err(dev, "%s power up timeout with status: 0x%x\n",
ctrl->subsys_id == IPU_IS ? "IS" : "PS", val);
- goto out_power;
+ return ret;
}

dev_dbg(dev, "%s power up successfully. status: 0x%x\n",
ctrl->subsys_id == IPU_IS ? "IS" : "PS", val);
-out_power:
- mutex_unlock(&isp->buttress.power_mutex);

- return ret;
+ return 0;
}

static int ipu8_buttress_powerdown(struct device *dev,
@@ -679,7 +670,7 @@ static int ipu8_buttress_powerdown(struct device *dev,
if (!ctrl)
return 0;

- mutex_lock(&isp->buttress.power_mutex);
+ guard(mutex)(&isp->buttress.power_mutex);
exp_sts = ctrl->pwr_sts_off << ctrl->pwr_sts_shift;

if (ctrl->subsys_id == IPU_PS)
@@ -712,7 +703,6 @@ static int ipu8_buttress_powerdown(struct device *dev,
if (val & ctrl->own_clk_ack)
writel(0, isp->base + BUTTRESS_REG_PS_PLL_ENABLE);
}
- mutex_unlock(&isp->buttress.power_mutex);

return ret;
}
@@ -852,12 +842,10 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
return 0;
}

- mutex_lock(&b->auth_mutex);
+ guard(mutex)(&b->auth_mutex);

- if (ipu_buttress_auth_done(isp)) {
- ret = 0;
- goto out_unlock;
- }
+ if (ipu_buttress_auth_done(isp))
+ return 0;

/*
* BUTTRESS_REG_FW_SOURCE_BASE needs to be set with FW CPD
@@ -879,7 +867,7 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
BUTTRESS_CSE2IUDATA0_IPC_BOOT_LOAD_DONE);
if (ret) {
dev_err(dev, "CSE boot_load failed\n");
- goto out_unlock;
+ return ret;
}

mask = BUTTRESS_SECURITY_CTL_FW_SETUP_MASK;
@@ -891,13 +879,12 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
BUTTRESS_CSE_BOOTLOAD_TIMEOUT_US);
if (ret) {
dev_err(dev, "CSE boot_load timeout\n");
- goto out_unlock;
+ return ret;
}

if ((data & mask) == fail) {
dev_err(dev, "CSE auth failed\n");
- ret = -EINVAL;
- goto out_unlock;
+ return -EINVAL;
}

ret = readl_poll_timeout(isp->base + BOOTLOADER_STATUS_OFFSET,
@@ -905,7 +892,7 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
BUTTRESS_CSE_BOOTLOAD_TIMEOUT_US);
if (ret) {
dev_err(dev, "Unexpected magic number 0x%x\n", data);
- goto out_unlock;
+ return ret;
}

/*
@@ -919,7 +906,7 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
BUTTRESS_CSE2IUDATA0_IPC_AUTH_RUN_DONE);
if (ret) {
dev_err(dev, "CSE authenticate_run failed\n");
- goto out_unlock;
+ return ret;
}

done = BUTTRESS_SECURITY_CTL_AUTH_DONE;
@@ -929,21 +916,17 @@ int ipu_buttress_authenticate(struct ipu7_device *isp)
BUTTRESS_CSE_AUTHENTICATE_TIMEOUT_US);
if (ret) {
dev_err(dev, "CSE authenticate timeout\n");
- goto out_unlock;
+ return ret;
}

if ((data & mask) == fail) {
dev_err(dev, "CSE boot_load failed\n");
- ret = -EINVAL;
- goto out_unlock;
+ return -EINVAL;
}

dev_info(dev, "CSE authenticate_run done\n");

-out_unlock:
- mutex_unlock(&b->auth_mutex);
-
- return ret;
+ return 0;
}

static int ipu_buttress_send_tsc_request(struct ipu7_device *isp)
--
2.43.0