[PATCH AUTOSEL 6.1 1/8] soundwire: dmi-quirks: add remapping for Intel 'Rooks County' NUC M15

[PATCH AUTOSEL 6.1 1/8] soundwire: dmi-quirks: add remapping for Intel 'Rooks County' NUC M15

[Sasha Levin]

From: Eugene Huang <eugene.huang99@gmail.com>

[ Upstream commit 01b33e284ca28cc977bdcfb23be2c719f2139175 ]

Same DSDT problem as the HP Omen 16-k0005TX, except rt1316 amp is on
link2.

Link: https://github.com/thesofproject/linux/issues/4088
Signed-off-by: Eugene Huang <eugene.huang99@gmail.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20230314090618.498716-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/soundwire/dmi-quirks.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/soundwire/dmi-quirks.c b/drivers/soundwire/dmi-quirks.c
index 7969881f126dc..58ea013fa918a 100644
--- a/drivers/soundwire/dmi-quirks.c
+++ b/drivers/soundwire/dmi-quirks.c
@@ -73,6 +73,23 @@ static const struct adr_remap hp_omen_16[] = {
 	{}
 };
 
+/*
+ * Intel NUC M15 LAPRC510 and LAPRC710
+ */
+static const struct adr_remap intel_rooks_county[] = {
+	/* rt711-sdca on link0 */
+	{
+		0x000020025d071100ull,
+		0x000030025d071101ull
+	},
+	/* rt1316-sdca on link2 */
+	{
+		0x000120025d071100ull,
+		0x000230025d131601ull
+	},
+	{}
+};
+
 static const struct dmi_system_id adr_remap_quirk_table[] = {
 	/* TGL devices */
 	{
@@ -98,6 +115,14 @@ static const struct dmi_system_id adr_remap_quirk_table[] = {
 		},
 		.driver_data = (void *)intel_tgl_bios,
 	},
+	{
+		/* quirk used for NUC15 'Rooks County' LAPRC510 and LAPRC710 skews */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Intel(R) Client Systems"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "LAPRC"),
+		},
+		.driver_data = (void *)intel_rooks_county,
+	},
 	{
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc"),
-- 
2.39.2

[PATCH AUTOSEL 6.1 2/8] phy: st: miphy28lp: use _poll_timeout functions for waits

[Sasha Levin]

From: Alain Volmat <avolmat@me.com>

[ Upstream commit e3be4dd2c8d8aabfd2c3127d0e2e5754d3ae82d6 ]

This commit introduces _poll_timeout functions usage instead of
wait loops waiting for a status bit.

Signed-off-by: Alain Volmat <avolmat@me.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20230210224309.98452-1-avolmat@me.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/phy/st/phy-miphy28lp.c | 42 ++++++++--------------------------
 1 file changed, 10 insertions(+), 32 deletions(-)

diff --git a/drivers/phy/st/phy-miphy28lp.c b/drivers/phy/st/phy-miphy28lp.c
index 068160a34f5cc..e30305b77f0d1 100644
--- a/drivers/phy/st/phy-miphy28lp.c
+++ b/drivers/phy/st/phy-miphy28lp.c
@@ -9,6 +9,7 @@
 
 #include <linux/platform_device.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
@@ -484,19 +485,11 @@ static inline void miphy28lp_pcie_config_gen(struct miphy28lp_phy *miphy_phy)
 
 static inline int miphy28lp_wait_compensation(struct miphy28lp_phy *miphy_phy)
 {
-	unsigned long finish = jiffies + 5 * HZ;
 	u8 val;
 
 	/* Waiting for Compensation to complete */
-	do {
-		val = readb_relaxed(miphy_phy->base + MIPHY_COMP_FSM_6);
-
-		if (time_after_eq(jiffies, finish))
-			return -EBUSY;
-		cpu_relax();
-	} while (!(val & COMP_DONE));
-
-	return 0;
+	return readb_relaxed_poll_timeout(miphy_phy->base + MIPHY_COMP_FSM_6,
+					  val, val & COMP_DONE, 1, 5 * USEC_PER_SEC);
 }
 
 
@@ -805,7 +798,6 @@ static inline void miphy28lp_configure_usb3(struct miphy28lp_phy *miphy_phy)
 
 static inline int miphy_is_ready(struct miphy28lp_phy *miphy_phy)
 {
-	unsigned long finish = jiffies + 5 * HZ;
 	u8 mask = HFC_PLL | HFC_RDY;
 	u8 val;
 
@@ -816,21 +808,14 @@ static inline int miphy_is_ready(struct miphy28lp_phy *miphy_phy)
 	if (miphy_phy->type == PHY_TYPE_SATA)
 		mask |= PHY_RDY;
 
-	do {
-		val = readb_relaxed(miphy_phy->base + MIPHY_STATUS_1);
-		if ((val & mask) != mask)
-			cpu_relax();
-		else
-			return 0;
-	} while (!time_after_eq(jiffies, finish));
-
-	return -EBUSY;
+	return readb_relaxed_poll_timeout(miphy_phy->base + MIPHY_STATUS_1,
+					  val, (val & mask) == mask, 1,
+					  5 * USEC_PER_SEC);
 }
 
 static int miphy_osc_is_ready(struct miphy28lp_phy *miphy_phy)
 {
 	struct miphy28lp_dev *miphy_dev = miphy_phy->phydev;
-	unsigned long finish = jiffies + 5 * HZ;
 	u32 val;
 
 	if (!miphy_phy->osc_rdy)
@@ -839,17 +824,10 @@ static int miphy_osc_is_ready(struct miphy28lp_phy *miphy_phy)
 	if (!miphy_phy->syscfg_reg[SYSCFG_STATUS])
 		return -EINVAL;
 
-	do {
-		regmap_read(miphy_dev->regmap,
-				miphy_phy->syscfg_reg[SYSCFG_STATUS], &val);
-
-		if ((val & MIPHY_OSC_RDY) != MIPHY_OSC_RDY)
-			cpu_relax();
-		else
-			return 0;
-	} while (!time_after_eq(jiffies, finish));
-
-	return -EBUSY;
+	return regmap_read_poll_timeout(miphy_dev->regmap,
+					miphy_phy->syscfg_reg[SYSCFG_STATUS],
+					val, val & MIPHY_OSC_RDY, 1,
+					5 * USEC_PER_SEC);
 }
 
 static int miphy28lp_get_resource_byname(struct device_node *child,
-- 
2.39.2

[PATCH AUTOSEL 6.1 3/8] soundwire: qcom: gracefully handle too many ports in DT

[Sasha Levin]

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

[ Upstream commit 2367e0ecb498764e95cfda691ff0828f7d25f9a4 ]

There are two issues related to the number of ports coming from
Devicetree when exceeding in total QCOM_SDW_MAX_PORTS.  Both lead to
incorrect memory accesses:
1. With DTS having too big value of input or output ports, the driver,
   when copying port parameters from local/stack arrays into 'pconfig'
   array in 'struct qcom_swrm_ctrl', will iterate over their sizes.

2. If DTS also has too many parameters for these ports (e.g.
   qcom,ports-sinterval-low), the driver will overflow buffers on the
   stack when reading these properties from DTS.

Add a sanity check so incorrect DTS will not cause kernel memory
corruption.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230222144412.237832-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/soundwire/qcom.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index cee2b22231410..c535da166ca1d 100644
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -1209,6 +1209,9 @@ static int qcom_swrm_get_port_config(struct qcom_swrm_ctrl *ctrl)
 	ctrl->num_dout_ports = val;
 
 	nports = ctrl->num_dout_ports + ctrl->num_din_ports;
+	if (nports > QCOM_SDW_MAX_PORTS)
+		return -EINVAL;
+
 	/* Valid port numbers are from 1-14, so mask out port 0 explicitly */
 	set_bit(0, &ctrl->dout_port_mask);
 	set_bit(0, &ctrl->din_port_mask);
-- 
2.39.2

[PATCH AUTOSEL 6.1 4/8] soundwire: bus: Fix unbalanced pm_runtime_put() causing usage count underflow

[Sasha Levin]

From: Richard Fitzgerald <rf@opensource.cirrus.com>

[ Upstream commit e9537962519e88969f5f69cd0571eb4f6984403c ]

This reverts commit
443a98e649b4 ("soundwire: bus: use pm_runtime_resume_and_get()")

Change calls to pm_runtime_resume_and_get() back to pm_runtime_get_sync().
This fixes a usage count underrun caused by doing a pm_runtime_put() even
though pm_runtime_resume_and_get() returned an error.

The three affected functions ignore -EACCES error from trying to get
pm_runtime, and carry on, including a put at the end of the function.
But pm_runtime_resume_and_get() does not increment the usage count if it
returns an error. So in the -EACCES case you must not call
pm_runtime_put().

The documentation for pm_runtime_get_sync() says:
 "Consider using pm_runtime_resume_and_get() ...  as this is likely to
 result in cleaner code."

In this case I don't think it results in cleaner code because the
pm_runtime_put() at the end of the function would have to be conditional on
the return value from pm_runtime_resume_and_get() at the top of the
function.

pm_runtime_get_sync() doesn't have this problem because it always
increments the count, so always needs a put. The code can just flow through
and do the pm_runtime_put() unconditionally.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20230406134640.8582-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/soundwire/bus.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 76515c33e639e..4fd221d0cc818 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -571,9 +571,11 @@ int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 {
 	int ret;
 
-	ret = pm_runtime_resume_and_get(&slave->dev);
-	if (ret < 0 && ret != -EACCES)
+	ret = pm_runtime_get_sync(&slave->dev);
+	if (ret < 0 && ret != -EACCES) {
+		pm_runtime_put_noidle(&slave->dev);
 		return ret;
+	}
 
 	ret = sdw_nread_no_pm(slave, addr, count, val);
 
@@ -595,9 +597,11 @@ int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 {
 	int ret;
 
-	ret = pm_runtime_resume_and_get(&slave->dev);
-	if (ret < 0 && ret != -EACCES)
+	ret = pm_runtime_get_sync(&slave->dev);
+	if (ret < 0 && ret != -EACCES) {
+		pm_runtime_put_noidle(&slave->dev);
 		return ret;
+	}
 
 	ret = sdw_nwrite_no_pm(slave, addr, count, val);
 
@@ -1565,9 +1569,10 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave)
 
 	sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
 
-	ret = pm_runtime_resume_and_get(&slave->dev);
+	ret = pm_runtime_get_sync(&slave->dev);
 	if (ret < 0 && ret != -EACCES) {
 		dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
+		pm_runtime_put_noidle(&slave->dev);
 		return ret;
 	}
 
-- 
2.39.2

[PATCH AUTOSEL 6.1 5/8] mfd: intel_soc_pmic_chtwc: Add Lenovo Yoga Book X90F to intel_cht_wc_models

[Sasha Levin]

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit ded99b89d25fd73a1d7bd910378e0339fd9d4c4a ]

The Android Lenovo Yoga Book X90F / X90L uses the same charger / fuelgauge
setup as the already supported Windows Lenovo Yoga Book X91F/L, add
a DMI match for this to intel_cht_wc_models with driver_data
set to INTEL_CHT_WC_LENOVO_YOGABOOK1.

When the quirk for the X91F/L was initially added it was written to
also apply to the X90F/L but this does not work because the Android
version of the Yoga Book uses completely different DMI strings.
Also adjust the X91F/L quirk to reflect that it only applies to
the X91F/L models.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230301095402.28582-1-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/mfd/intel_soc_pmic_chtwc.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/intel_soc_pmic_chtwc.c b/drivers/mfd/intel_soc_pmic_chtwc.c
index 9216f0d34206c..a82b7cb661b7b 100644
--- a/drivers/mfd/intel_soc_pmic_chtwc.c
+++ b/drivers/mfd/intel_soc_pmic_chtwc.c
@@ -159,11 +159,19 @@ static const struct dmi_system_id cht_wc_model_dmi_ids[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "Mipad2"),
 		},
 	}, {
-		/* Lenovo Yoga Book X90F / X91F / X91L */
+		/* Lenovo Yoga Book X90F / X90L */
 		.driver_data = (void *)(long)INTEL_CHT_WC_LENOVO_YOGABOOK1,
 		.matches = {
-			/* Non exact match to match all versions */
-			DMI_MATCH(DMI_PRODUCT_NAME, "Lenovo YB1-X9"),
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "CHERRYVIEW D1 PLATFORM"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "YETI-11"),
+		},
+	}, {
+		/* Lenovo Yoga Book X91F / X91L */
+		.driver_data = (void *)(long)INTEL_CHT_WC_LENOVO_YOGABOOK1,
+		.matches = {
+			/* Non exact match to match F + L versions */
+			DMI_MATCH(DMI_PRODUCT_NAME, "Lenovo YB1-X91"),
 		},
 	},
 	{ }
-- 
2.39.2

[PATCH AUTOSEL 6.1 6/8] mfd: dln2: Fix memory leak in dln2_probe()

[Sasha Levin]

From: Qiang Ning <qning0106@126.com>

[ Upstream commit 96da8f148396329ba769246cb8ceaa35f1ddfc48 ]

When dln2_setup_rx_urbs() in dln2_probe() fails, error out_free forgets
to call usb_put_dev() to decrease the refcount of dln2->usb_dev.

Fix this by adding usb_put_dev() in the error handling code of
dln2_probe().

Signed-off-by: Qiang Ning <qning0106@126.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230330024353.4503-1-qning0106@126.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/mfd/dln2.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mfd/dln2.c b/drivers/mfd/dln2.c
index 6cd0b0c752d6e..c3149729cec2e 100644
--- a/drivers/mfd/dln2.c
+++ b/drivers/mfd/dln2.c
@@ -827,6 +827,7 @@ static int dln2_probe(struct usb_interface *interface,
 	dln2_stop_rx_urbs(dln2);
 
 out_free:
+	usb_put_dev(dln2->usb_dev);
 	dln2_free(dln2);
 
 	return ret;
-- 
2.39.2

[PATCH AUTOSEL 6.1 7/8] mfd: intel-lpss: Add Intel Meteor Lake PCH-S LPSS PCI IDs

[Sasha Levin]

From: Jarkko Nikula <jarkko.nikula@linux.intel.com>

[ Upstream commit 72d4a1683741ee578da0e265886e6a7f3d42266c ]

Add Intel Meteor Lake PCH-S also called as Meteor Point-S LPSS PCI IDs.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230330132618.4108665-1-jarkko.nikula@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/mfd/intel-lpss-pci.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
index dde31c50a6320..699f44ffff0e4 100644
--- a/drivers/mfd/intel-lpss-pci.c
+++ b/drivers/mfd/intel-lpss-pci.c
@@ -447,6 +447,21 @@ static const struct pci_device_id intel_lpss_pci_ids[] = {
 	{ PCI_VDEVICE(INTEL, 0x7e79), (kernel_ulong_t)&bxt_i2c_info },
 	{ PCI_VDEVICE(INTEL, 0x7e7a), (kernel_ulong_t)&bxt_i2c_info },
 	{ PCI_VDEVICE(INTEL, 0x7e7b), (kernel_ulong_t)&bxt_i2c_info },
+	/* MTP-S */
+	{ PCI_VDEVICE(INTEL, 0x7f28), (kernel_ulong_t)&bxt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x7f29), (kernel_ulong_t)&bxt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x7f2a), (kernel_ulong_t)&tgl_info },
+	{ PCI_VDEVICE(INTEL, 0x7f2b), (kernel_ulong_t)&tgl_info },
+	{ PCI_VDEVICE(INTEL, 0x7f4c), (kernel_ulong_t)&bxt_i2c_info },
+	{ PCI_VDEVICE(INTEL, 0x7f4d), (kernel_ulong_t)&bxt_i2c_info },
+	{ PCI_VDEVICE(INTEL, 0x7f4e), (kernel_ulong_t)&bxt_i2c_info },
+	{ PCI_VDEVICE(INTEL, 0x7f4f), (kernel_ulong_t)&bxt_i2c_info },
+	{ PCI_VDEVICE(INTEL, 0x7f5c), (kernel_ulong_t)&bxt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x7f5d), (kernel_ulong_t)&bxt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x7f5e), (kernel_ulong_t)&tgl_info },
+	{ PCI_VDEVICE(INTEL, 0x7f5f), (kernel_ulong_t)&tgl_info },
+	{ PCI_VDEVICE(INTEL, 0x7f7a), (kernel_ulong_t)&bxt_i2c_info },
+	{ PCI_VDEVICE(INTEL, 0x7f7b), (kernel_ulong_t)&bxt_i2c_info },
 	/* LKF */
 	{ PCI_VDEVICE(INTEL, 0x98a8), (kernel_ulong_t)&bxt_uart_info },
 	{ PCI_VDEVICE(INTEL, 0x98a9), (kernel_ulong_t)&bxt_uart_info },
-- 
2.39.2

[PATCH AUTOSEL 6.1 8/8] parisc: Replace regular spinlock with spin_trylock on panic path

[Sasha Levin]

From: "Guilherme G. Piccoli" <gpiccoli@igalia.com>

[ Upstream commit 829632dae8321787525ee37dc4828bbe6edafdae ]

The panic notifiers' callbacks execute in an atomic context, with
interrupts/preemption disabled, and all CPUs not running the panic
function are off, so it's very dangerous to wait on a regular
spinlock, there's a risk of deadlock.

Refactor the panic notifier of parisc/power driver to make use
of spin_trylock - for that, we've added a second version of the
soft-power function. Also, some comments were reorganized and
trailing white spaces, useless header inclusion and blank lines
were removed.

Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeroen Roovers <jer@xs4all.nl>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/parisc/include/asm/pdc.h |  1 +
 arch/parisc/kernel/firmware.c | 27 +++++++++++++++++++++++----
 drivers/parisc/power.c        | 16 ++++++++++------
 3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/arch/parisc/include/asm/pdc.h b/arch/parisc/include/asm/pdc.h
index fcbcf9a96c111..77622558bf651 100644
--- a/arch/parisc/include/asm/pdc.h
+++ b/arch/parisc/include/asm/pdc.h
@@ -80,6 +80,7 @@ int pdc_do_firm_test_reset(unsigned long ftc_bitmap);
 int pdc_do_reset(void);
 int pdc_soft_power_info(unsigned long *power_reg);
 int pdc_soft_power_button(int sw_control);
+int pdc_soft_power_button_panic(int sw_control);
 void pdc_io_reset(void);
 void pdc_io_reset_devices(void);
 int pdc_iodc_getc(void);
diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c
index bd325f2b5349e..3e051a973e9b2 100644
--- a/arch/parisc/kernel/firmware.c
+++ b/arch/parisc/kernel/firmware.c
@@ -1232,15 +1232,18 @@ int __init pdc_soft_power_info(unsigned long *power_reg)
 }
 
 /*
- * pdc_soft_power_button - Control the soft power button behaviour
- * @sw_control: 0 for hardware control, 1 for software control 
+ * pdc_soft_power_button{_panic} - Control the soft power button behaviour
+ * @sw_control: 0 for hardware control, 1 for software control
  *
  *
  * This PDC function places the soft power button under software or
  * hardware control.
- * Under software control the OS may control to when to allow to shut 
- * down the system. Under hardware control pressing the power button 
+ * Under software control the OS may control to when to allow to shut
+ * down the system. Under hardware control pressing the power button
  * powers off the system immediately.
+ *
+ * The _panic version relies on spin_trylock to prevent deadlock
+ * on panic path.
  */
 int pdc_soft_power_button(int sw_control)
 {
@@ -1254,6 +1257,22 @@ int pdc_soft_power_button(int sw_control)
 	return retval;
 }
 
+int pdc_soft_power_button_panic(int sw_control)
+{
+	int retval;
+	unsigned long flags;
+
+	if (!spin_trylock_irqsave(&pdc_lock, flags)) {
+		pr_emerg("Couldn't enable soft power button\n");
+		return -EBUSY; /* ignored by the panic notifier */
+	}
+
+	retval = mem_pdc_call(PDC_SOFT_POWER, PDC_SOFT_POWER_ENABLE, __pa(pdc_result), sw_control);
+	spin_unlock_irqrestore(&pdc_lock, flags);
+
+	return retval;
+}
+
 /*
  * pdc_io_reset - Hack to avoid overlapping range registers of Bridges devices.
  * Primarily a problem on T600 (which parisc-linux doesn't support) but
diff --git a/drivers/parisc/power.c b/drivers/parisc/power.c
index 456776bd8ee66..6f5e5f0230d39 100644
--- a/drivers/parisc/power.c
+++ b/drivers/parisc/power.c
@@ -37,7 +37,6 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
-#include <linux/notifier.h>
 #include <linux/panic_notifier.h>
 #include <linux/reboot.h>
 #include <linux/sched/signal.h>
@@ -175,16 +174,21 @@ static void powerfail_interrupt(int code, void *x)
 
 
 
-/* parisc_panic_event() is called by the panic handler.
- * As soon as a panic occurs, our tasklets above will not be
- * executed any longer. This function then re-enables the 
- * soft-power switch and allows the user to switch off the system
+/*
+ * parisc_panic_event() is called by the panic handler.
+ *
+ * As soon as a panic occurs, our tasklets above will not
+ * be executed any longer. This function then re-enables
+ * the soft-power switch and allows the user to switch off
+ * the system. We rely in pdc_soft_power_button_panic()
+ * since this version spin_trylocks (instead of regular
+ * spinlock), preventing deadlocks on panic path.
  */
 static int parisc_panic_event(struct notifier_block *this,
 		unsigned long event, void *ptr)
 {
 	/* re-enable the soft-power switch */
-	pdc_soft_power_button(0);
+	pdc_soft_power_button_panic(0);
 	return NOTIFY_DONE;
 }
 
-- 
2.39.2