soc: qcom: smd: Make callback pass channel reference

By passing the smd channel reference to the callback, rather than the
smd device, we can open additional smd channels from sub-devices of smd
devices.

Also updates the two smd clients today found in mainline.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>

drivers/soc/qcom/smd-rpm.c

@@ -33,6 +33,7 @@
  */
 struct qcom_smd_rpm {
 	struct qcom_smd_channel *rpm_channel;
+	struct device *dev;
 
 	struct completion ack;
 	struct mutex lock;
@@ -149,14 +150,14 @@ int qcom_rpm_smd_write(struct qcom_smd_rpm *rpm,
 }
 EXPORT_SYMBOL(qcom_rpm_smd_write);
 
-static int qcom_smd_rpm_callback(struct qcom_smd_device *qsdev,
+static int qcom_smd_rpm_callback(struct qcom_smd_channel *channel,
 				 const void *data,
 				 size_t count)
 {
 	const struct qcom_rpm_header *hdr = data;
 	size_t hdr_length = le32_to_cpu(hdr->length);
 	const struct qcom_rpm_message *msg;
-	struct qcom_smd_rpm *rpm = dev_get_drvdata(&qsdev->dev);
+	struct qcom_smd_rpm *rpm = qcom_smd_get_drvdata(channel);
 	const u8 *buf = data + sizeof(struct qcom_rpm_header);
 	const u8 *end = buf + hdr_length;
 	char msgbuf[32];
@@ -165,7 +166,7 @@ static int qcom_smd_rpm_callback(struct qcom_smd_device *qsdev,
 
 	if (le32_to_cpu(hdr->service_type) != RPM_SERVICE_TYPE_REQUEST ||
 	    hdr_length < sizeof(struct qcom_rpm_message)) {
-		dev_err(&qsdev->dev, "invalid request\n");
+		dev_err(rpm->dev, "invalid request\n");
 		return 0;
 	}
 
@@ -206,7 +207,9 @@ static int qcom_smd_rpm_probe(struct qcom_smd_device *sdev)
 	mutex_init(&rpm->lock);
 	init_completion(&rpm->ack);
 
+	rpm->dev = &sdev->dev;
 	rpm->rpm_channel = sdev->channel;
+	qcom_smd_set_drvdata(sdev->channel, rpm);
 
 	dev_set_drvdata(&sdev->dev, rpm);
 

drivers/soc/qcom/smd.c

@@ -194,6 +194,8 @@ struct qcom_smd_channel {
 
 	int pkt_size;
 
+	void *drvdata;
+
 	struct list_head list;
 	struct list_head dev_list;
 };
@@ -513,7 +515,6 @@ static void qcom_smd_channel_advance(struct qcom_smd_channel *channel,
  */
 static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel)
 {
-	struct qcom_smd_device *qsdev = channel->qsdev;
 	unsigned tail;
 	size_t len;
 	void *ptr;
@@ -533,7 +534,7 @@ static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel)
 		len = channel->pkt_size;
 	}
 
-	ret = channel->cb(qsdev, ptr, len);
+	ret = channel->cb(channel, ptr, len);
 	if (ret < 0)
 		return ret;
 
@@ -1034,6 +1035,18 @@ int qcom_smd_driver_register(struct qcom_smd_driver *qsdrv)
 }
 EXPORT_SYMBOL(qcom_smd_driver_register);
 
+void *qcom_smd_get_drvdata(struct qcom_smd_channel *channel)
+{
+	return channel->drvdata;
+}
+EXPORT_SYMBOL(qcom_smd_get_drvdata);
+
+void qcom_smd_set_drvdata(struct qcom_smd_channel *channel, void *data)
+{
+	channel->drvdata = data;
+}
+EXPORT_SYMBOL(qcom_smd_set_drvdata);
+
 /**
  * qcom_smd_driver_unregister - unregister a smd driver
  * @qsdrv:	qcom_smd_driver struct
@@ -1079,12 +1092,13 @@ qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name)
  * Returns a channel handle on success, or -EPROBE_DEFER if the channel isn't
  * ready.
  */
-struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_device *sdev,
+struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_channel *parent,
 					       const char *name,
 					       qcom_smd_cb_t cb)
 {
 	struct qcom_smd_channel *channel;
-	struct qcom_smd_edge *edge = sdev->channel->edge;
+	struct qcom_smd_device *sdev = parent->qsdev;
+	struct qcom_smd_edge *edge = parent->edge;
 	int ret;
 
 	/* Wait up to HZ for the channel to appear */

drivers/soc/qcom/wcnss_ctrl.c

@@ -100,17 +100,17 @@ struct wcnss_download_nv_resp {
 
 /**
  * wcnss_ctrl_smd_callback() - handler from SMD responses
- * @qsdev:	smd device handle
+ * @channel:	smd channel handle
  * @data:	pointer to the incoming data packet
  * @count:	size of the incoming data packet
  *
  * Handles any incoming packets from the remote WCNSS_CTRL service.
  */
-static int wcnss_ctrl_smd_callback(struct qcom_smd_device *qsdev,
+static int wcnss_ctrl_smd_callback(struct qcom_smd_channel *channel,
 				   const void *data,
 				   size_t count)
 {
-	struct wcnss_ctrl *wcnss = dev_get_drvdata(&qsdev->dev);
+	struct wcnss_ctrl *wcnss = qcom_smd_get_drvdata(channel);
 	const struct wcnss_download_nv_resp *nvresp;
 	const struct wcnss_version_resp *version;
 	const struct wcnss_msg_hdr *hdr = data;
@@ -246,7 +246,7 @@ static int wcnss_ctrl_probe(struct qcom_smd_device *sdev)
 	init_completion(&wcnss->ack);
 	INIT_WORK(&wcnss->download_nv_work, wcnss_download_nv);
 
-	dev_set_drvdata(&sdev->dev, wcnss);
+	qcom_smd_set_drvdata(sdev->channel, wcnss);
 
 	return wcnss_request_version(wcnss);
 }

include/linux/soc/qcom/smd.h

@@ -26,7 +26,7 @@ struct qcom_smd_device {
 	struct qcom_smd_channel *channel;
 };
 
-typedef int (*qcom_smd_cb_t)(struct qcom_smd_device *, const void *, size_t);
+typedef int (*qcom_smd_cb_t)(struct qcom_smd_channel *, const void *, size_t);
 
 /**
  * struct qcom_smd_driver - smd driver struct
@@ -50,13 +50,16 @@ struct qcom_smd_driver {
 int qcom_smd_driver_register(struct qcom_smd_driver *drv);
 void qcom_smd_driver_unregister(struct qcom_smd_driver *drv);
 
+void *qcom_smd_get_drvdata(struct qcom_smd_channel *channel);
+void qcom_smd_set_drvdata(struct qcom_smd_channel *channel, void *data);
+
 #define module_qcom_smd_driver(__smd_driver) \
 	module_driver(__smd_driver, qcom_smd_driver_register, \
 		      qcom_smd_driver_unregister)
 
 int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len);
 
-struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_device *sdev,
+struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_channel *channel,
 					       const char *name,
 					       qcom_smd_cb_t cb);