[v8,3/7] soc: qcom: add QCOM PBS driver
Commit Message
Add the Qualcomm PBS (Programmable Boot Sequencer) driver. The QCOM PBS
driver supports configuring software PBS trigger events through PBS RAM
on Qualcomm Technologies, Inc (QTI) PMICs.
Signed-off-by: Anjelique Melendez <quic_amelende@quicinc.com>
---
drivers/soc/qcom/Kconfig | 9 ++
drivers/soc/qcom/Makefile | 1 +
drivers/soc/qcom/qcom-pbs.c | 243 ++++++++++++++++++++++++++++++
include/linux/soc/qcom/qcom-pbs.h | 30 ++++
4 files changed, 283 insertions(+)
create mode 100644 drivers/soc/qcom/qcom-pbs.c
create mode 100644 include/linux/soc/qcom/qcom-pbs.h
Comments
On Thu, 21 Dec 2023, Anjelique Melendez wrote:
> Add the Qualcomm PBS (Programmable Boot Sequencer) driver. The QCOM PBS
> driver supports configuring software PBS trigger events through PBS RAM
> on Qualcomm Technologies, Inc (QTI) PMICs.
>
> Signed-off-by: Anjelique Melendez <quic_amelende@quicinc.com>
> ---
> drivers/soc/qcom/Kconfig | 9 ++
> drivers/soc/qcom/Makefile | 1 +
> drivers/soc/qcom/qcom-pbs.c | 243 ++++++++++++++++++++++++++++++
> include/linux/soc/qcom/qcom-pbs.h | 30 ++++
> 4 files changed, 283 insertions(+)
> create mode 100644 drivers/soc/qcom/qcom-pbs.c
> create mode 100644 include/linux/soc/qcom/qcom-pbs.h
This needs to be applied soon, or I'll have to remove all of the LEDS
patches, since the lack of include/linux/soc/qcom/qcom-pbs.h is causing
build failures.
On Thu, Dec 21, 2023 at 10:58:33AM -0800, Anjelique Melendez wrote:
> diff --git a/drivers/soc/qcom/qcom-pbs.c b/drivers/soc/qcom/qcom-pbs.c
[..]
> +static int qcom_pbs_wait_for_ack(struct pbs_dev *pbs, u8 bit_pos)
> +{
> + int ret, retries = 2000, delay = 1100;
retries and delay are not variable, please use defines instead.
> + unsigned int val;
> +
> + ret = regmap_read_poll_timeout(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> + val, val & BIT(bit_pos), delay, delay * retries);
> +
> + if (ret < 0) {
> + dev_err(pbs->dev, "Timeout for PBS ACK/NACK for bit %u\n", bit_pos);
> + return -ETIMEDOUT;
> + }
> +
> + if (val == PBS_CLIENT_SCRATCH2_ERROR) {
> + ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
> + dev_err(pbs->dev, "NACK from PBS for bit %u\n", bit_pos);
> + return -EINVAL;
> + }
> +
> + dev_dbg(pbs->dev, "PBS sequence for bit %u executed!\n", bit_pos);
> + return 0;
> +}
> +
> +/**
> + * qcom_pbs_trigger_event() - Trigger the PBS RAM sequence
> + * @pbs: Pointer to PBS device
> + * @bitmap: bitmap
> + *
> + * This function is used to trigger the PBS RAM sequence to be
> + * executed by the client driver.
> + *
> + * The PBS trigger sequence involves
> + * 1. setting the PBS sequence bit in PBS_CLIENT_SCRATCH1
> + * 2. Initiating the SW PBS trigger
> + * 3. Checking the equivalent bit in PBS_CLIENT_SCRATCH2 for the
> + * completion of the sequence.
> + * 4. If PBS_CLIENT_SCRATCH2 == 0xFF, the PBS sequence failed to execute
> + *
> + * Returns: 0 on success, < 0 on failure
Return: without the 's' is the appropriate form here.
> + */
> +int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
> +{
> + unsigned int val;
> + u16 bit_pos;
> + int ret;
> +
> + if (!bitmap) {
> + dev_err(pbs->dev, "Invalid bitmap passed by client\n");
No one is going to spot that hidden in the kernel log, and if someone
sees it it does not give an indication to which client it is that's
broken (if there are multiple clients...)
Instead do:
if (WARN_ON(!bitmap))
return -EINVAL;
> + return -EINVAL;
> + }
> +
> + if (IS_ERR_OR_NULL(pbs))
> + return -EINVAL;
> +
> + mutex_lock(&pbs->lock);
> + ret = regmap_read(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, &val);
> + if (ret < 0)
> + goto out;
> +
> + if (val == PBS_CLIENT_SCRATCH2_ERROR) {
> + /* PBS error - clear SCRATCH2 register */
> + ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
> + if (ret < 0)
> + goto out;
> + }
> +
> + for (bit_pos = 0; bit_pos < 8; bit_pos++) {
> + if (!(bitmap & BIT(bit_pos)))
> + continue;
> +
> + /* Clear the PBS sequence bit position */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> + BIT(bit_pos), 0);
> + if (ret < 0)
> + goto error;
> +
> + /* Set the PBS sequence bit position */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
> + BIT(bit_pos), BIT(bit_pos));
> + if (ret < 0)
> + goto error;
> +
> + /* Initiate the SW trigger */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_TRIG_CTL,
> + PBS_CLIENT_SW_TRIG_BIT, PBS_CLIENT_SW_TRIG_BIT);
> + if (ret < 0)
> + goto error;
> +
> + ret = qcom_pbs_wait_for_ack(pbs, bit_pos);
> + if (ret < 0)
> + goto error;
In the case that this fails, you're jumping to error, which clears all
of SCRATCH1, but you're leaving SCRATCH2 untouched.
> +
> + /* Clear the PBS sequence bit position */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
> + BIT(bit_pos), 0);
> + if (ret < 0)
> + goto error;
Does it make sense to handle this error by jumping to error and trying
to clear it once more - while leaving SCRATCH2?
Perhaps you should just ignore the errors from clearing SCRATCH1 and
SCRATCH2? You where able to trigger the PBS and you got your ack...
> +
> + /* Clear the PBS sequence bit position */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> + BIT(bit_pos), 0);
> + if (ret < 0)
> + goto error;
> + }
> +
> +error:
We're passing "error" in the successful case as well, please name this
"out_clear_scratch1" (or something) instead, to not confuse the reader.
> + /* Clear all the requested bitmap */
> + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1, bitmap, 0);
> +
> +out:
> + mutex_unlock(&pbs->lock);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(qcom_pbs_trigger_event);
> +
> +/**
> + * get_pbs_client_device() - Get the PBS device used by client
> + * @dev: Client device
> + *
> + * This function is used to get the PBS device that is being
> + * used by the client.
> + *
> + * Returns: pbs_dev on success, ERR_PTR on failure
Return:
Regards,
Bjorn
Intentional generic top-post reply.
Please work quickly to resolve Bjorn's comments.
I'm being hounded over a broken LEDs tree due to the missing headerfile.
/end
On Tue, 30 Jan 2024, Bjorn Andersson wrote:
> On Thu, Dec 21, 2023 at 10:58:33AM -0800, Anjelique Melendez wrote:
> > diff --git a/drivers/soc/qcom/qcom-pbs.c b/drivers/soc/qcom/qcom-pbs.c
> [..]
> > +static int qcom_pbs_wait_for_ack(struct pbs_dev *pbs, u8 bit_pos)
> > +{
> > + int ret, retries = 2000, delay = 1100;
>
> retries and delay are not variable, please use defines instead.
>
> > + unsigned int val;
> > +
> > + ret = regmap_read_poll_timeout(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> > + val, val & BIT(bit_pos), delay, delay * retries);
> > +
> > + if (ret < 0) {
> > + dev_err(pbs->dev, "Timeout for PBS ACK/NACK for bit %u\n", bit_pos);
> > + return -ETIMEDOUT;
> > + }
> > +
> > + if (val == PBS_CLIENT_SCRATCH2_ERROR) {
> > + ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
> > + dev_err(pbs->dev, "NACK from PBS for bit %u\n", bit_pos);
> > + return -EINVAL;
> > + }
> > +
> > + dev_dbg(pbs->dev, "PBS sequence for bit %u executed!\n", bit_pos);
> > + return 0;
> > +}
> > +
> > +/**
> > + * qcom_pbs_trigger_event() - Trigger the PBS RAM sequence
> > + * @pbs: Pointer to PBS device
> > + * @bitmap: bitmap
> > + *
> > + * This function is used to trigger the PBS RAM sequence to be
> > + * executed by the client driver.
> > + *
> > + * The PBS trigger sequence involves
> > + * 1. setting the PBS sequence bit in PBS_CLIENT_SCRATCH1
> > + * 2. Initiating the SW PBS trigger
> > + * 3. Checking the equivalent bit in PBS_CLIENT_SCRATCH2 for the
> > + * completion of the sequence.
> > + * 4. If PBS_CLIENT_SCRATCH2 == 0xFF, the PBS sequence failed to execute
> > + *
> > + * Returns: 0 on success, < 0 on failure
>
> Return: without the 's' is the appropriate form here.
>
> > + */
> > +int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
> > +{
> > + unsigned int val;
> > + u16 bit_pos;
> > + int ret;
> > +
> > + if (!bitmap) {
> > + dev_err(pbs->dev, "Invalid bitmap passed by client\n");
>
> No one is going to spot that hidden in the kernel log, and if someone
> sees it it does not give an indication to which client it is that's
> broken (if there are multiple clients...)
>
> Instead do:
>
> if (WARN_ON(!bitmap))
> return -EINVAL;
>
> > + return -EINVAL;
> > + }
> > +
> > + if (IS_ERR_OR_NULL(pbs))
> > + return -EINVAL;
> > +
> > + mutex_lock(&pbs->lock);
> > + ret = regmap_read(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, &val);
> > + if (ret < 0)
> > + goto out;
> > +
> > + if (val == PBS_CLIENT_SCRATCH2_ERROR) {
> > + /* PBS error - clear SCRATCH2 register */
> > + ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
> > + if (ret < 0)
> > + goto out;
> > + }
> > +
> > + for (bit_pos = 0; bit_pos < 8; bit_pos++) {
> > + if (!(bitmap & BIT(bit_pos)))
> > + continue;
> > +
> > + /* Clear the PBS sequence bit position */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> > + BIT(bit_pos), 0);
> > + if (ret < 0)
> > + goto error;
> > +
> > + /* Set the PBS sequence bit position */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
> > + BIT(bit_pos), BIT(bit_pos));
> > + if (ret < 0)
> > + goto error;
> > +
> > + /* Initiate the SW trigger */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_TRIG_CTL,
> > + PBS_CLIENT_SW_TRIG_BIT, PBS_CLIENT_SW_TRIG_BIT);
> > + if (ret < 0)
> > + goto error;
> > +
> > + ret = qcom_pbs_wait_for_ack(pbs, bit_pos);
> > + if (ret < 0)
> > + goto error;
>
> In the case that this fails, you're jumping to error, which clears all
> of SCRATCH1, but you're leaving SCRATCH2 untouched.
>
> > +
> > + /* Clear the PBS sequence bit position */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
> > + BIT(bit_pos), 0);
> > + if (ret < 0)
> > + goto error;
>
> Does it make sense to handle this error by jumping to error and trying
> to clear it once more - while leaving SCRATCH2?
>
> Perhaps you should just ignore the errors from clearing SCRATCH1 and
> SCRATCH2? You where able to trigger the PBS and you got your ack...
>
> > +
> > + /* Clear the PBS sequence bit position */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
> > + BIT(bit_pos), 0);
> > + if (ret < 0)
> > + goto error;
> > + }
> > +
> > +error:
>
> We're passing "error" in the successful case as well, please name this
> "out_clear_scratch1" (or something) instead, to not confuse the reader.
>
> > + /* Clear all the requested bitmap */
> > + ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1, bitmap, 0);
> > +
> > +out:
> > + mutex_unlock(&pbs->lock);
> > +
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(qcom_pbs_trigger_event);
> > +
> > +/**
> > + * get_pbs_client_device() - Get the PBS device used by client
> > + * @dev: Client device
> > + *
> > + * This function is used to get the PBS device that is being
> > + * used by the client.
> > + *
> > + * Returns: pbs_dev on success, ERR_PTR on failure
>
> Return:
>
> Regards,
> Bjorn
On 1/31/2024 12:58 AM, Lee Jones wrote:
> Intentional generic top-post reply.
>
> Please work quickly to resolve Bjorn's comments.
>
> I'm being hounded over a broken LEDs tree due to the missing headerfile.
>
> /end
>
Updated changes for QCOM PBS driver with Bjorn's comments can be found
at new series:
https://lore.kernel.org/all/20240201204421.16992-2-quic_amelende@quicinc.com/
On Wed, Jan 31, 2024 at 08:58:42AM +0000, Lee Jones wrote:
> Intentional generic top-post reply.
>
> Please work quickly to resolve Bjorn's comments.
>
> I'm being hounded over a broken LEDs tree due to the missing headerfile.
>
I've merged the updated patches into the qcom tree.
I presume though that you'd like to have this build issue resolved in
your tree as well. Please feel free to pull the branch:
20240201204421.16992-2-quic_amelende@quicinc.com (5b2dd77be1d85ac3a8be3749f5605bf0830e2998)
from https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux.git
Regards,
Bjorn
On Thu, 01 Feb 2024, Bjorn Andersson wrote:
> On Wed, Jan 31, 2024 at 08:58:42AM +0000, Lee Jones wrote:
> > Intentional generic top-post reply.
> >
> > Please work quickly to resolve Bjorn's comments.
> >
> > I'm being hounded over a broken LEDs tree due to the missing headerfile.
> >
>
> I've merged the updated patches into the qcom tree.
>
> I presume though that you'd like to have this build issue resolved in
> your tree as well. Please feel free to pull the branch:
>
> 20240201204421.16992-2-quic_amelende@quicinc.com (5b2dd77be1d85ac3a8be3749f5605bf0830e2998)
>
> from https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux.git
Great, thanks.
On Thu, 01 Feb 2024, Bjorn Andersson wrote:
> On Wed, Jan 31, 2024 at 08:58:42AM +0000, Lee Jones wrote:
> > Intentional generic top-post reply.
> >
> > Please work quickly to resolve Bjorn's comments.
> >
> > I'm being hounded over a broken LEDs tree due to the missing headerfile.
> >
>
> I've merged the updated patches into the qcom tree.
>
> I presume though that you'd like to have this build issue resolved in
> your tree as well. Please feel free to pull the branch:
>
> 20240201204421.16992-2-quic_amelende@quicinc.com (5b2dd77be1d85ac3a8be3749f5605bf0830e2998)
>
> from https://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux.git
Pulled, thanks.
@@ -254,4 +254,13 @@ config QCOM_INLINE_CRYPTO_ENGINE
tristate
select QCOM_SCM
+config QCOM_PBS
+ tristate "PBS trigger support for Qualcomm Technologies, Inc. PMICS"
+ depends on SPMI
+ help
+ This driver supports configuring software programmable boot sequencer (PBS)
+ trigger event through PBS RAM on Qualcomm Technologies, Inc. PMICs.
+ This module provides the APIs to the client drivers that wants to send the
+ PBS trigger event to the PBS RAM.
+
endmenu
@@ -32,3 +32,4 @@ obj-$(CONFIG_QCOM_KRYO_L2_ACCESSORS) += kryo-l2-accessors.o
obj-$(CONFIG_QCOM_ICC_BWMON) += icc-bwmon.o
qcom_ice-objs += ice.o
obj-$(CONFIG_QCOM_INLINE_CRYPTO_ENGINE) += qcom_ice.o
+obj-$(CONFIG_QCOM_PBS) += qcom-pbs.o
new file mode 100644
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/spmi.h>
+#include <linux/soc/qcom/qcom-pbs.h>
+
+#define PBS_CLIENT_TRIG_CTL 0x42
+#define PBS_CLIENT_SW_TRIG_BIT BIT(7)
+#define PBS_CLIENT_SCRATCH1 0x50
+#define PBS_CLIENT_SCRATCH2 0x51
+#define PBS_CLIENT_SCRATCH2_ERROR 0xFF
+
+struct pbs_dev {
+ struct device *dev;
+ struct regmap *regmap;
+ struct mutex lock;
+ struct device_link *link;
+
+ u32 base;
+};
+
+static int qcom_pbs_wait_for_ack(struct pbs_dev *pbs, u8 bit_pos)
+{
+ int ret, retries = 2000, delay = 1100;
+ unsigned int val;
+
+ ret = regmap_read_poll_timeout(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ val, val & BIT(bit_pos), delay, delay * retries);
+
+ if (ret < 0) {
+ dev_err(pbs->dev, "Timeout for PBS ACK/NACK for bit %u\n", bit_pos);
+ return -ETIMEDOUT;
+ }
+
+ if (val == PBS_CLIENT_SCRATCH2_ERROR) {
+ ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
+ dev_err(pbs->dev, "NACK from PBS for bit %u\n", bit_pos);
+ return -EINVAL;
+ }
+
+ dev_dbg(pbs->dev, "PBS sequence for bit %u executed!\n", bit_pos);
+ return 0;
+}
+
+/**
+ * qcom_pbs_trigger_event() - Trigger the PBS RAM sequence
+ * @pbs: Pointer to PBS device
+ * @bitmap: bitmap
+ *
+ * This function is used to trigger the PBS RAM sequence to be
+ * executed by the client driver.
+ *
+ * The PBS trigger sequence involves
+ * 1. setting the PBS sequence bit in PBS_CLIENT_SCRATCH1
+ * 2. Initiating the SW PBS trigger
+ * 3. Checking the equivalent bit in PBS_CLIENT_SCRATCH2 for the
+ * completion of the sequence.
+ * 4. If PBS_CLIENT_SCRATCH2 == 0xFF, the PBS sequence failed to execute
+ *
+ * Returns: 0 on success, < 0 on failure
+ */
+int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
+{
+ unsigned int val;
+ u16 bit_pos;
+ int ret;
+
+ if (!bitmap) {
+ dev_err(pbs->dev, "Invalid bitmap passed by client\n");
+ return -EINVAL;
+ }
+
+ if (IS_ERR_OR_NULL(pbs))
+ return -EINVAL;
+
+ mutex_lock(&pbs->lock);
+ ret = regmap_read(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, &val);
+ if (ret < 0)
+ goto out;
+
+ if (val == PBS_CLIENT_SCRATCH2_ERROR) {
+ /* PBS error - clear SCRATCH2 register */
+ ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
+ if (ret < 0)
+ goto out;
+ }
+
+ for (bit_pos = 0; bit_pos < 8; bit_pos++) {
+ if (!(bitmap & BIT(bit_pos)))
+ continue;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+
+ /* Set the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
+ BIT(bit_pos), BIT(bit_pos));
+ if (ret < 0)
+ goto error;
+
+ /* Initiate the SW trigger */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_TRIG_CTL,
+ PBS_CLIENT_SW_TRIG_BIT, PBS_CLIENT_SW_TRIG_BIT);
+ if (ret < 0)
+ goto error;
+
+ ret = qcom_pbs_wait_for_ack(pbs, bit_pos);
+ if (ret < 0)
+ goto error;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+ }
+
+error:
+ /* Clear all the requested bitmap */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1, bitmap, 0);
+
+out:
+ mutex_unlock(&pbs->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(qcom_pbs_trigger_event);
+
+/**
+ * get_pbs_client_device() - Get the PBS device used by client
+ * @dev: Client device
+ *
+ * This function is used to get the PBS device that is being
+ * used by the client.
+ *
+ * Returns: pbs_dev on success, ERR_PTR on failure
+ */
+struct pbs_dev *get_pbs_client_device(struct device *dev)
+{
+ struct device_node *pbs_dev_node;
+ struct platform_device *pdev;
+ struct pbs_dev *pbs;
+
+ pbs_dev_node = of_parse_phandle(dev->of_node, "qcom,pbs", 0);
+ if (!pbs_dev_node) {
+ dev_err(dev, "Missing qcom,pbs property\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ pdev = of_find_device_by_node(pbs_dev_node);
+ if (!pdev) {
+ dev_err(dev, "Unable to find PBS dev_node\n");
+ pbs = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ pbs = platform_get_drvdata(pdev);
+ if (!pbs) {
+ dev_err(dev, "Cannot get pbs instance from %s\n", dev_name(&pdev->dev));
+ platform_device_put(pdev);
+ pbs = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ pbs->link = device_link_add(dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
+ if (!pbs->link) {
+ dev_err(&pdev->dev, "Failed to create device link to consumer %s\n", dev_name(dev));
+ platform_device_put(pdev);
+ pbs = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+out:
+ of_node_put(pbs_dev_node);
+ return pbs;
+}
+EXPORT_SYMBOL_GPL(get_pbs_client_device);
+
+static int qcom_pbs_probe(struct platform_device *pdev)
+{
+ struct pbs_dev *pbs;
+ u32 val;
+ int ret;
+
+ pbs = devm_kzalloc(&pdev->dev, sizeof(*pbs), GFP_KERNEL);
+ if (!pbs)
+ return -ENOMEM;
+
+ pbs->dev = &pdev->dev;
+ pbs->regmap = dev_get_regmap(pbs->dev->parent, NULL);
+ if (!pbs->regmap) {
+ dev_err(pbs->dev, "Couldn't get parent's regmap\n");
+ return -EINVAL;
+ }
+
+ ret = device_property_read_u32(pbs->dev, "reg", &val);
+ if (ret < 0) {
+ dev_err(pbs->dev, "Couldn't find reg, ret = %d\n", ret);
+ return ret;
+ }
+ pbs->base = val;
+ mutex_init(&pbs->lock);
+
+ platform_set_drvdata(pdev, pbs);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_pbs_match_table[] = {
+ { .compatible = "qcom,pbs" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qcom_pbs_match_table);
+
+static struct platform_driver qcom_pbs_driver = {
+ .driver = {
+ .name = "qcom-pbs",
+ .of_match_table = qcom_pbs_match_table,
+ },
+ .probe = qcom_pbs_probe,
+};
+module_platform_driver(qcom_pbs_driver)
+
+MODULE_DESCRIPTION("QCOM PBS DRIVER");
+MODULE_LICENSE("GPL");
new file mode 100644
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _QCOM_PBS_H
+#define _QCOM_PBS_H
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+struct device_node;
+struct pbs_dev;
+
+#if IS_ENABLED(CONFIG_QCOM_PBS)
+int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap);
+struct pbs_dev *get_pbs_client_device(struct device *client_dev);
+#else
+static inline int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
+{
+ return -ENODEV;
+}
+
+static inline struct pbs_dev *get_pbs_client_device(struct device *client_dev)
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+
+#endif