[PATCH v2 2/4] Input: exc3000: query and show type, model and firmware revision info

From: Lucas Stach <l.stach@pengutronix.de>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: linux-input@vger.kernel.org, kernel@pengutronix.de,
	patchwork-lst@pengutronix.de
Subject: [PATCH v2 2/4] Input: exc3000: query and show type, model and firmware revision info
Date: Fri, 13 Mar 2020 15:33:43 +0100	[thread overview]
Message-ID: <20200313143345.28565-2-l.stach@pengutronix.de> (raw)
In-Reply-To: <20200313143345.28565-1-l.stach@pengutronix.de>

It's useful to have this information in the log, as differences in behavior
can be tied to the controller firmare.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
---
v2:
- don't request IRQ before input device is set up
- add timeout to wait for vendor request response
- add error handling to memory allocations
---
 drivers/input/touchscreen/exc3000.c | 115 ++++++++++++++++++++++++++++
 1 file changed, 115 insertions(+)

diff --git a/drivers/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c
index 3458d02310dd..8d170bac182d 100644
--- a/drivers/input/touchscreen/exc3000.c
+++ b/drivers/input/touchscreen/exc3000.c
@@ -22,7 +22,9 @@
 #define EXC3000_NUM_SLOTS		10
 #define EXC3000_SLOTS_PER_FRAME		5
 #define EXC3000_LEN_FRAME		66
+#define EXC3000_LEN_VENDOR_REQUEST	68
 #define EXC3000_LEN_POINT		10
+#define EXC3000_VENDOR_EVENT		3
 #define EXC3000_MT_EVENT		6
 #define EXC3000_TIMEOUT_MS		100
 
@@ -32,6 +34,9 @@ struct exc3000_data {
 	struct touchscreen_properties prop;
 	struct timer_list timer;
 	u8 buf[2 * EXC3000_LEN_FRAME];
+	struct mutex vendor_data_lock;
+	struct completion vendor_data_done;
+	char *type, *model, *fw_rev;
 };
 
 static void exc3000_report_slots(struct input_dev *input,
@@ -136,6 +141,13 @@ static int exc3000_handle_mt_event(struct exc3000_data *data)
 	return ret;
 }
 
+static int exc3000_handle_vendor_event(struct exc3000_data *data)
+{
+	complete(&data->vendor_data_done);
+
+	return 0;
+}
+
 static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
 {
 	struct exc3000_data *data = dev_id;
@@ -153,6 +165,9 @@ static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
 		case EXC3000_MT_EVENT:
 			exc3000_handle_mt_event(data);
 			break;
+		case EXC3000_VENDOR_EVENT:
+			exc3000_handle_vendor_event(data);
+			break;
 		default:
 			break;
 	}
@@ -161,6 +176,100 @@ static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static int exc3000_vendor_data_request(struct exc3000_data *data, u8 *request,
+				       u8 request_len, u8 *response)
+{
+	u8 buf[EXC3000_LEN_VENDOR_REQUEST] = { 0x67, 0x00, 0x42, 0x00, 0x03 };
+	int ret;
+
+	mutex_lock(&data->vendor_data_lock);
+
+	reinit_completion(&data->vendor_data_done);
+
+	buf[5] = request_len;
+	memcpy(&buf[6], request, request_len);
+
+	ret = i2c_master_send(data->client, buf, EXC3000_LEN_VENDOR_REQUEST);
+	if (ret < 0)
+		goto out_unlock;
+
+	if (response) {
+		ret = wait_for_completion_timeout(&data->vendor_data_done,
+						  10 * HZ);
+		if (!ret) {
+			ret = -ETIMEDOUT;
+			goto out_unlock;
+		}
+		memcpy(response, &data->buf[4], data->buf[3]);
+		ret = data->buf[3];
+	}
+
+out_unlock:
+	mutex_unlock(&data->vendor_data_lock);
+
+	return ret;
+}
+static int exc3000_populate_device_info(struct exc3000_data *data)
+{
+	struct device *dev = &data->client->dev;
+	u8 response[EXC3000_LEN_FRAME];
+	int ret;
+
+	/* query type info */
+	ret = exc3000_vendor_data_request(data, (u8[]){0x46}, 1, response);
+	if (ret < 0)
+		return -ENODEV;
+
+	data->type = devm_kmemdup(dev, &response[1], ret - 1, GFP_KERNEL);
+	if (!data->type)
+		return -ENOMEM;
+
+	/* query model info */
+	ret = exc3000_vendor_data_request(data, (u8[]){0x45}, 1, response);
+	if (ret < 0)
+		return -ENODEV;
+
+	data->model = devm_kmemdup(dev, &response[1], ret - 1, GFP_KERNEL);
+	if (!data->model)
+		return -ENOMEM;
+
+	/* query bootloader info */
+	ret = exc3000_vendor_data_request(data,
+					  (u8[]){0x39, 0x02}, 2, response);
+	if (ret < 0)
+		return -ENODEV;
+
+	/*
+	 * If the bootloader version is non-zero then the device is in
+	 * bootloader mode and won't answer a query for the application FW
+	 * version, so we just use the bootloader version info.
+	 */
+	if (response[2] || response[3]) {
+		char bl_version[8];
+
+		snprintf(bl_version, 8, "%d.%d", response[2], response[3]);
+		data->fw_rev = devm_kmemdup(dev, bl_version,
+					    strlen(bl_version), GFP_KERNEL);
+	} else {
+		/* query application firmware version */
+		ret = exc3000_vendor_data_request(data,
+						  (u8[]){0x44}, 1, response);
+		if (ret < 0)
+			return -ENODEV;
+
+		data->fw_rev = devm_kmemdup(dev, &response[1],
+					    ret - 1, GFP_KERNEL);
+	}
+	if (!data->fw_rev)
+		return -ENOMEM;
+
+	dev_info(&data->client->dev,
+		 "found type %s, model %s, firmware revision %s",
+		 data->type, data->model, data->fw_rev);
+
+	return 0;
+}
+
 static int exc3000_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -174,6 +283,8 @@ static int exc3000_probe(struct i2c_client *client,
 
 	data->client = client;
 	timer_setup(&data->timer, exc3000_timer, 0);
+	mutex_init(&data->vendor_data_lock);
+	init_completion(&data->vendor_data_done);
 
 	input = devm_input_allocate_device(&client->dev);
 	if (!input)
@@ -203,6 +314,10 @@ static int exc3000_probe(struct i2c_client *client,
 	if (error)
 		return error;
 
+	error = exc3000_populate_device_info(data);
+	if (error)
+		return error;
+
 	return 0;
 }
 
-- 
2.20.1

