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* [PATCH V4 0/2] soc: qcom: aoss: Expose send for generic usecase
@ 2021-06-14 10:21 Deepak Kumar Singh
  2021-06-14 10:21 ` [PATCH V4 1/2] " Deepak Kumar Singh
  2021-06-14 10:21 ` [PATCH V4 2/2] soc: qcom: aoss: Add debugfs entry Deepak Kumar Singh
  0 siblings, 2 replies; 5+ messages in thread
From: Deepak Kumar Singh @ 2021-06-14 10:21 UTC (permalink / raw)
  To: bjorn.andersson, clew, sibis, manivannan.sadhasivam
  Cc: linux-kernel, linux-arm-msm, linux-remoteproc, Deepak Kumar Singh

[Changes from V3]
Add qmp_put declaration in qcom_aoss.h

Deepak Kumar Singh (2):
  soc: qcom: aoss: Expose send for generic usecase
  soc: qcom: aoss: Add debugfs entry

 drivers/soc/qcom/qcom_aoss.c       | 109 ++++++++++++++++++++++++++++++++++++-
 include/linux/soc/qcom/qcom_aoss.h |  38 +++++++++++++
 2 files changed, 145 insertions(+), 2 deletions(-)
 create mode 100644 include/linux/soc/qcom/qcom_aoss.h

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH V4 1/2] soc: qcom: aoss: Expose send for generic usecase
  2021-06-14 10:21 [PATCH V4 0/2] soc: qcom: aoss: Expose send for generic usecase Deepak Kumar Singh
@ 2021-06-14 10:21 ` Deepak Kumar Singh
  2021-06-14 10:21 ` [PATCH V4 2/2] soc: qcom: aoss: Add debugfs entry Deepak Kumar Singh
  1 sibling, 0 replies; 5+ messages in thread
From: Deepak Kumar Singh @ 2021-06-14 10:21 UTC (permalink / raw)
  To: bjorn.andersson, clew, sibis, manivannan.sadhasivam
  Cc: linux-kernel, linux-arm-msm, linux-remoteproc,
	Deepak Kumar Singh, Andy Gross

Not all upcoming usecases will have an interface to allow the aoss
driver to hook onto. Expose the send api and create a get function to
enable drivers to send their own messages to aoss.

Signed-off-by: Chris Lew <clew@codeaurora.org>
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
---
 drivers/soc/qcom/qcom_aoss.c       | 70 ++++++++++++++++++++++++++++++++++++--
 include/linux/soc/qcom/qcom_aoss.h | 38 +++++++++++++++++++++
 2 files changed, 106 insertions(+), 2 deletions(-)
 create mode 100644 include/linux/soc/qcom/qcom_aoss.h

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index 53acb94..cd75d4d 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -8,10 +8,12 @@
 #include <linux/io.h>
 #include <linux/mailbox_client.h>
 #include <linux/module.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/thermal.h>
 #include <linux/slab.h>
+#include <linux/soc/qcom/qcom_aoss.h>
 
 #define QMP_DESC_MAGIC			0x0
 #define QMP_DESC_VERSION		0x4
@@ -61,6 +63,7 @@ struct qmp_cooling_device {
  * @mbox_chan: mailbox channel used to ring the doorbell on transmit
  * @offset: offset within @msgram where messages should be written
  * @size: maximum size of the messages to be transmitted
+ * @orphan: tarcks whether qmp handle is valid
  * @event: wait_queue for synchronization with the IRQ
  * @tx_lock: provides synchronization between multiple callers of qmp_send()
  * @qdss_clk: QDSS clock hw struct
@@ -76,6 +79,8 @@ struct qmp {
 
 	size_t offset;
 	size_t size;
+	atomic_t  orphan;
+	struct kref refcount;
 
 	wait_queue_head_t event;
 
@@ -223,11 +228,17 @@ static bool qmp_message_empty(struct qmp *qmp)
  *
  * Return: 0 on success, negative errno on failure
  */
-static int qmp_send(struct qmp *qmp, const void *data, size_t len)
+int qmp_send(struct qmp *qmp, const void *data, size_t len)
 {
 	long time_left;
 	int ret;
 
+	if (WARN_ON(IS_ERR_OR_NULL(qmp) || !data))
+		return -EINVAL;
+
+	if (atomic_read(&qmp->orphan))
+		return -EINVAL;
+
 	if (WARN_ON(len + sizeof(u32) > qmp->size))
 		return -EINVAL;
 
@@ -261,6 +272,7 @@ static int qmp_send(struct qmp *qmp, const void *data, size_t len)
 
 	return ret;
 }
+EXPORT_SYMBOL(qmp_send);
 
 static int qmp_qdss_clk_prepare(struct clk_hw *hw)
 {
@@ -515,6 +527,54 @@ static void qmp_cooling_devices_remove(struct qmp *qmp)
 		thermal_cooling_device_unregister(qmp->cooling_devs[i].cdev);
 }
 
+/**
+ * qmp_get() - get a qmp handle from a device
+ * @dev: client device pointer
+ *
+ * Return: handle to qmp device on success, ERR_PTR() on failure
+ */
+struct qmp *qmp_get(struct device *dev)
+{
+	struct platform_device *pdev;
+	struct device_node *np;
+	struct qmp *qmp;
+
+	if (!dev || !dev->of_node)
+		return ERR_PTR(-EINVAL);
+
+	np = of_parse_phandle(dev->of_node, "qcom,qmp", 0);
+	if (!np)
+		return ERR_PTR(-ENODEV);
+
+	pdev = of_find_device_by_node(np);
+	of_node_put(np);
+	if (!pdev)
+		return ERR_PTR(-EINVAL);
+
+	qmp = platform_get_drvdata(pdev);
+	platform_device_put(pdev);
+
+	if (qmp)
+		kref_get(&qmp->refcount);
+
+	return qmp ? qmp : ERR_PTR(-EPROBE_DEFER);
+}
+EXPORT_SYMBOL(qmp_get);
+
+static void qmp_handle_release(struct kref *ref)
+{
+	struct qmp *qmp = container_of(ref, struct qmp, refcount);
+
+	kfree(qmp);
+}
+
+void qmp_put(struct qmp *qmp)
+{
+	if (!IS_ERR_OR_NULL(qmp))
+		kref_put(&qmp->refcount, qmp_handle_release);
+}
+EXPORT_SYMBOL(qmp_put);
+
 static int qmp_probe(struct platform_device *pdev)
 {
 	struct resource *res;
@@ -522,13 +582,14 @@ static int qmp_probe(struct platform_device *pdev)
 	int irq;
 	int ret;
 
-	qmp = devm_kzalloc(&pdev->dev, sizeof(*qmp), GFP_KERNEL);
+	qmp = kzalloc(sizeof(*qmp), GFP_KERNEL);
 	if (!qmp)
 		return -ENOMEM;
 
 	qmp->dev = &pdev->dev;
 	init_waitqueue_head(&qmp->event);
 	mutex_init(&qmp->tx_lock);
+	kref_init(&qmp->refcount);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	qmp->msgram = devm_ioremap_resource(&pdev->dev, res);
@@ -569,6 +630,8 @@ static int qmp_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, qmp);
 
+	atomic_set(&qmp->orphan, 0);
+
 	return 0;
 
 err_remove_qdss_clk:
@@ -577,6 +640,7 @@ static int qmp_probe(struct platform_device *pdev)
 	qmp_close(qmp);
 err_free_mbox:
 	mbox_free_channel(qmp->mbox_chan);
+	kfree(qmp);
 
 	return ret;
 }
@@ -590,7 +654,9 @@ static int qmp_remove(struct platform_device *pdev)
 	qmp_cooling_devices_remove(qmp);
 
 	qmp_close(qmp);
+	atomic_set(&qmp->orphan, 1);
 	mbox_free_channel(qmp->mbox_chan);
+	kref_put(&qmp->refcount, qmp_handle_release);
 
 	return 0;
 }
diff --git a/include/linux/soc/qcom/qcom_aoss.h b/include/linux/soc/qcom/qcom_aoss.h
new file mode 100644
index 0000000..a8d8f07
--- /dev/null
+++ b/include/linux/soc/qcom/qcom_aoss.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __QCOM_AOSS_H__
+#define __QCOM_AOSS_H__
+
+#include <linux/err.h>
+#include <linux/device.h>
+
+struct qmp;
+
+#if IS_ENABLED(CONFIG_QCOM_AOSS_QMP)
+
+int qmp_send(struct qmp *qmp, const void *data, size_t len);
+struct qmp *qmp_get(struct device *dev);
+void qmp_put(struct qmp *qmp);
+
+#else
+
+static inline int qmp_send(struct qmp *qmp, const void *data, size_t len)
+{
+	return -ENODEV;
+}
+
+static inline struct qmp *qmp_get(struct device *dev)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void qmp_put(struct qmp *qmp)
+{
+}
+
+#endif
+
+#endif
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH V4 2/2] soc: qcom: aoss: Add debugfs entry
  2021-06-14 10:21 [PATCH V4 0/2] soc: qcom: aoss: Expose send for generic usecase Deepak Kumar Singh
  2021-06-14 10:21 ` [PATCH V4 1/2] " Deepak Kumar Singh
@ 2021-06-14 10:21 ` Deepak Kumar Singh
  1 sibling, 0 replies; 5+ messages in thread
From: Deepak Kumar Singh @ 2021-06-14 10:21 UTC (permalink / raw)
  To: bjorn.andersson, clew, sibis, manivannan.sadhasivam
  Cc: linux-kernel, linux-arm-msm, linux-remoteproc,
	Deepak Kumar Singh, Andy Gross

It can be useful to control the different power states of various
parts of hardware for device testing. Add a debugfs node for qmp so
messages can be sent to aoss for debugging and testing purposes.

Signed-off-by: Chris Lew <clew@codeaurora.org>
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
---
 drivers/soc/qcom/qcom_aoss.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index cd75d4d..438adc9 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -4,6 +4,7 @@
  */
 #include <dt-bindings/power/qcom-aoss-qmp.h>
 #include <linux/clk-provider.h>
+#include <linux/debugfs.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/mailbox_client.h>
@@ -89,6 +90,9 @@ struct qmp {
 	struct clk_hw qdss_clk;
 	struct genpd_onecell_data pd_data;
 	struct qmp_cooling_device *cooling_devs;
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	struct dentry *debugfs_file;
+#endif /* CONFIG_DEBUG_FS */
 };
 
 struct qmp_pd {
@@ -575,6 +579,32 @@ void qmp_put(struct qmp *qmp)
 }
 EXPORT_SYMBOL(qmp_put);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+static ssize_t aoss_dbg_write(struct file *file, const char __user *userstr,
+			      size_t len, loff_t *pos)
+{
+	struct qmp *qmp = file->private_data;
+	char buf[QMP_MSG_LEN] = {};
+	int ret;
+
+	if (!len || len >= QMP_MSG_LEN)
+		return len;
+
+	ret  = copy_from_user(buf, userstr, len);
+	if (ret)
+		return len;
+
+	ret = qmp_send(qmp, buf, QMP_MSG_LEN);
+
+	return ret ? ret : len;
+}
+
+static const struct file_operations aoss_dbg_fops = {
+	.open = simple_open,
+	.write = aoss_dbg_write,
+};
+#endif /* CONFIG_DEBUG_FS */
+
 static int qmp_probe(struct platform_device *pdev)
 {
 	struct resource *res;
@@ -632,6 +662,11 @@ static int qmp_probe(struct platform_device *pdev)
 
 	atomic_set(&qmp->orphan, 0);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	qmp->debugfs_file = debugfs_create_file("aoss_send_message", 0220, NULL,
+						qmp, &aoss_dbg_fops);
+#endif /* CONFIG_DEBUG_FS */
+
 	return 0;
 
 err_remove_qdss_clk:
@@ -649,6 +684,10 @@ static int qmp_remove(struct platform_device *pdev)
 {
 	struct qmp *qmp = platform_get_drvdata(pdev);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	debugfs_remove(qmp->debugfs_file);
+#endif /* CONFIG_DEBUG_FS */
+
 	qmp_qdss_clk_remove(qmp);
 	qmp_pd_remove(qmp);
 	qmp_cooling_devices_remove(qmp);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH v4 2/2] soc: qcom: aoss: Add debugfs entry
  2021-06-09 11:18 ` [PATCH v4 2/2] soc: qcom: aoss: Add debugfs entry Sibi Sankar
@ 2021-08-04 19:06   ` Bjorn Andersson
  0 siblings, 0 replies; 5+ messages in thread
From: Bjorn Andersson @ 2021-08-04 19:06 UTC (permalink / raw)
  To: Sibi Sankar
  Cc: agross, linux-kernel, linux-arm-msm, swboyd,
	manivannan.sadhasivam, Deepak Kumar Singh, Chris Lew

On Wed 09 Jun 06:18 CDT 2021, Sibi Sankar wrote:

> From: Deepak Kumar Singh <deesin@codeaurora.org>
> 
> It can be useful to control the different power states of various
> parts of hardware for device testing. Add a debugfs node for qmp so
> messages can be sent to aoss for debugging and testing purposes.
> 

I thought I replied to this patch, but can't find the reply...

> Signed-off-by: Chris Lew <clew@codeaurora.org>
> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
> Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
> ---
>  drivers/soc/qcom/qcom_aoss.c | 39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
> index e8f48760bac8..998ee7605eb2 100644
> --- a/drivers/soc/qcom/qcom_aoss.c
> +++ b/drivers/soc/qcom/qcom_aoss.c
> @@ -4,6 +4,7 @@
>   */
>  #include <dt-bindings/power/qcom-aoss-qmp.h>
>  #include <linux/clk-provider.h>
> +#include <linux/debugfs.h>
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/mailbox_client.h>
> @@ -89,6 +90,9 @@ struct qmp {
>  	struct clk_hw qdss_clk;
>  	struct genpd_onecell_data pd_data;
>  	struct qmp_cooling_device *cooling_devs;
> +#if IS_ENABLED(CONFIG_DEBUG_FS)
> +	struct dentry *debugfs_file;
> +#endif /* CONFIG_DEBUG_FS */
>  };
>  
>  struct qmp_pd {
> @@ -575,6 +579,32 @@ void qmp_put(struct qmp *qmp)
>  }
>  EXPORT_SYMBOL(qmp_put);
>  
> +#if IS_ENABLED(CONFIG_DEBUG_FS)
> +static ssize_t aoss_dbg_write(struct file *file, const char __user *userstr,
> +			      size_t len, loff_t *pos)
> +{
> +	struct qmp *qmp = file->private_data;
> +	char buf[QMP_MSG_LEN] = {};
> +	int ret;
> +
> +	if (!len || len >= QMP_MSG_LEN)
> +		return len;
> +
> +	ret  = copy_from_user(buf, userstr, len);
> +	if (ret)
> +		return len;
> +
> +	ret = qmp_send(qmp, buf, QMP_MSG_LEN);
> +
> +	return ret ? ret : len;
> +}
> +
> +static const struct file_operations aoss_dbg_fops = {
> +	.open = simple_open,
> +	.write = aoss_dbg_write,
> +};
> +#endif /* CONFIG_DEBUG_FS */
> +
>  static int qmp_probe(struct platform_device *pdev)
>  {
>  	struct resource *res;
> @@ -632,6 +662,11 @@ static int qmp_probe(struct platform_device *pdev)
>  
>  	atomic_set(&qmp->orphan, 0);
>  
> +#if IS_ENABLED(CONFIG_DEBUG_FS)
> +	qmp->debugfs_file = debugfs_create_file("aoss_send_message", 0220, NULL,
> +						qmp, &aoss_dbg_fops);
> +#endif /* CONFIG_DEBUG_FS */

You shouldn't need the guards, debugfs_create_file() is stubbed if
CONFIG_DEBUG_FS isn't set, so it's better to just rely on that.

Regards,
Bjorn

> +
>  	return 0;
>  
>  err_remove_qdss_clk:
> @@ -649,6 +684,10 @@ static int qmp_remove(struct platform_device *pdev)
>  {
>  	struct qmp *qmp = platform_get_drvdata(pdev);
>  
> +#if IS_ENABLED(CONFIG_DEBUG_FS)
> +	debugfs_remove(qmp->debugfs_file);
> +#endif /* CONFIG_DEBUG_FS */
> +
>  	qmp_qdss_clk_remove(qmp);
>  	qmp_pd_remove(qmp);
>  	qmp_cooling_devices_remove(qmp);
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH v4 2/2] soc: qcom: aoss: Add debugfs entry
  2021-06-09 11:18 [PATCH v4 0/2] soc: qcom: aoss: Expose send for generic usecase Sibi Sankar
@ 2021-06-09 11:18 ` Sibi Sankar
  2021-08-04 19:06   ` Bjorn Andersson
  0 siblings, 1 reply; 5+ messages in thread
From: Sibi Sankar @ 2021-06-09 11:18 UTC (permalink / raw)
  To: bjorn.andersson
  Cc: agross, linux-kernel, linux-arm-msm, swboyd,
	manivannan.sadhasivam, Deepak Kumar Singh, Chris Lew,
	Sibi Sankar

From: Deepak Kumar Singh <deesin@codeaurora.org>

It can be useful to control the different power states of various
parts of hardware for device testing. Add a debugfs node for qmp so
messages can be sent to aoss for debugging and testing purposes.

Signed-off-by: Chris Lew <clew@codeaurora.org>
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
---
 drivers/soc/qcom/qcom_aoss.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
index e8f48760bac8..998ee7605eb2 100644
--- a/drivers/soc/qcom/qcom_aoss.c
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -4,6 +4,7 @@
  */
 #include <dt-bindings/power/qcom-aoss-qmp.h>
 #include <linux/clk-provider.h>
+#include <linux/debugfs.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/mailbox_client.h>
@@ -89,6 +90,9 @@ struct qmp {
 	struct clk_hw qdss_clk;
 	struct genpd_onecell_data pd_data;
 	struct qmp_cooling_device *cooling_devs;
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	struct dentry *debugfs_file;
+#endif /* CONFIG_DEBUG_FS */
 };
 
 struct qmp_pd {
@@ -575,6 +579,32 @@ void qmp_put(struct qmp *qmp)
 }
 EXPORT_SYMBOL(qmp_put);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+static ssize_t aoss_dbg_write(struct file *file, const char __user *userstr,
+			      size_t len, loff_t *pos)
+{
+	struct qmp *qmp = file->private_data;
+	char buf[QMP_MSG_LEN] = {};
+	int ret;
+
+	if (!len || len >= QMP_MSG_LEN)
+		return len;
+
+	ret  = copy_from_user(buf, userstr, len);
+	if (ret)
+		return len;
+
+	ret = qmp_send(qmp, buf, QMP_MSG_LEN);
+
+	return ret ? ret : len;
+}
+
+static const struct file_operations aoss_dbg_fops = {
+	.open = simple_open,
+	.write = aoss_dbg_write,
+};
+#endif /* CONFIG_DEBUG_FS */
+
 static int qmp_probe(struct platform_device *pdev)
 {
 	struct resource *res;
@@ -632,6 +662,11 @@ static int qmp_probe(struct platform_device *pdev)
 
 	atomic_set(&qmp->orphan, 0);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	qmp->debugfs_file = debugfs_create_file("aoss_send_message", 0220, NULL,
+						qmp, &aoss_dbg_fops);
+#endif /* CONFIG_DEBUG_FS */
+
 	return 0;
 
 err_remove_qdss_clk:
@@ -649,6 +684,10 @@ static int qmp_remove(struct platform_device *pdev)
 {
 	struct qmp *qmp = platform_get_drvdata(pdev);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	debugfs_remove(qmp->debugfs_file);
+#endif /* CONFIG_DEBUG_FS */
+
 	qmp_qdss_clk_remove(qmp);
 	qmp_pd_remove(qmp);
 	qmp_cooling_devices_remove(qmp);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2021-08-04 19:06 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-06-14 10:21 [PATCH V4 0/2] soc: qcom: aoss: Expose send for generic usecase Deepak Kumar Singh
2021-06-14 10:21 ` [PATCH V4 1/2] " Deepak Kumar Singh
2021-06-14 10:21 ` [PATCH V4 2/2] soc: qcom: aoss: Add debugfs entry Deepak Kumar Singh
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2021-06-09 11:18 [PATCH v4 0/2] soc: qcom: aoss: Expose send for generic usecase Sibi Sankar
2021-06-09 11:18 ` [PATCH v4 2/2] soc: qcom: aoss: Add debugfs entry Sibi Sankar
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