Merge branch 'for-3.8/upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel...
[firefly-linux-kernel-4.4.55.git] / drivers / hid / i2c-hid / i2c-hid.c
index 3c8fe4673705f9e9ac22a87967478a6bedbb6e11..e766b5614ef59fcae45aaeff49a98df9de3e9693 100644 (file)
@@ -32,8 +32,8 @@
 #include <linux/list.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
-#include <linux/bug.h>
 #include <linux/hid.h>
+#include <linux/mutex.h>
 
 #include <linux/i2c/i2c-hid.h>
 
@@ -50,9 +50,11 @@ static bool debug;
 module_param(debug, bool, 0444);
 MODULE_PARM_DESC(debug, "print a lot of debug information");
 
-#define i2c_hid_dbg(ihid, fmt, arg...) \
-       if (debug)                      \
-               dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg)
+#define i2c_hid_dbg(ihid, fmt, arg...)                                   \
+do {                                                                     \
+       if (debug)                                                        \
+               dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
+} while (0)
 
 struct i2c_hid_desc {
        __le16 wHIDDescLength;
@@ -68,6 +70,7 @@ struct i2c_hid_desc {
        __le16 wVendorID;
        __le16 wProductID;
        __le16 wVersionID;
+       __le32 reserved;
 } __packed;
 
 struct i2c_hid_cmd {
@@ -103,22 +106,19 @@ static const struct i2c_hid_cmd hid_reset_cmd =           { I2C_HID_CMD(0x01),
                                                          .wait = true };
 static const struct i2c_hid_cmd hid_get_report_cmd =   { I2C_HID_CMD(0x02) };
 static const struct i2c_hid_cmd hid_set_report_cmd =   { I2C_HID_CMD(0x03) };
-static const struct i2c_hid_cmd hid_get_idle_cmd =     { I2C_HID_CMD(0x04) };
-static const struct i2c_hid_cmd hid_set_idle_cmd =     { I2C_HID_CMD(0x05) };
-static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
-static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
 static const struct i2c_hid_cmd hid_set_power_cmd =    { I2C_HID_CMD(0x08) };
-/* read/write data register */
-static const struct i2c_hid_cmd hid_data_cmd = {
-               .registerIndex = offsetof(struct i2c_hid_desc, wDataRegister),
-               .opcode = 0x00,
-               .length = 2 };
-/* write output reports */
-static const struct i2c_hid_cmd hid_out_cmd = {
-               .registerIndex = offsetof(struct i2c_hid_desc,
-                       wOutputRegister),
-               .opcode = 0x00,
-               .length = 2 };
+
+/*
+ * These definitions are not used here, but are defined by the spec.
+ * Keeping them here for documentation purposes.
+ *
+ * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
+ * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
+ * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
+ * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
+ */
+
+static DEFINE_MUTEX(i2c_hid_open_mut);
 
 /* The main device structure */
 struct i2c_hid {
@@ -138,8 +138,6 @@ struct i2c_hid {
 
        unsigned long           flags;          /* device flags */
 
-       int                     irq;            /* the interrupt line irq */
-
        wait_queue_head_t       wait;           /* For waiting the interrupt */
 };
 
@@ -247,7 +245,7 @@ static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
        if (ret) {
                dev_err(&client->dev,
                        "failed to retrieve report from device.\n");
-               return -EINVAL;
+               return ret;
        }
 
        return 0;
@@ -292,7 +290,7 @@ static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
                reportType, args, args_len, NULL, 0);
        if (ret) {
                dev_err(&client->dev, "failed to set a report to device.\n");
-               return -EINVAL;
+               return ret;
        }
 
        return data_len;
@@ -336,7 +334,7 @@ static int i2c_hid_hwreset(struct i2c_client *client)
        return 0;
 }
 
-static int i2c_hid_get_input(struct i2c_hid *ihid)
+static void i2c_hid_get_input(struct i2c_hid *ihid)
 {
        int ret, ret_size;
        int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
@@ -344,11 +342,11 @@ static int i2c_hid_get_input(struct i2c_hid *ihid)
        ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
        if (ret != size) {
                if (ret < 0)
-                       return ret;
+                       return;
 
                dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
                        __func__, ret, size);
-               return ret;
+               return;
        }
 
        ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
@@ -357,13 +355,13 @@ static int i2c_hid_get_input(struct i2c_hid *ihid)
                /* host or device initiated RESET completed */
                if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
                        wake_up(&ihid->wait);
-               return 0;
+               return;
        }
 
        if (ret_size > size) {
                dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
                        __func__, size, ret_size);
-               return -EIO;
+               return;
        }
 
        i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
@@ -372,7 +370,7 @@ static int i2c_hid_get_input(struct i2c_hid *ihid)
                hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
                                ret_size - 2, 1);
 
-       return 0;
+       return;
 }
 
 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
@@ -402,9 +400,10 @@ static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
        unsigned int size, ret_size;
 
        size = i2c_hid_get_report_length(report);
-       i2c_hid_get_report(client,
+       if (i2c_hid_get_report(client,
                        report->type == HID_FEATURE_REPORT ? 0x03 : 0x01,
-                       report->id, buffer, size);
+                       report->id, buffer, size))
+               return;
 
        i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, ihid->inbuf);
 
@@ -432,8 +431,10 @@ static void i2c_hid_init_reports(struct hid_device *hid)
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
 
-       if (!inbuf)
+       if (!inbuf) {
+               dev_err(&client->dev, "can not retrieve initial reports\n");
                return;
+       }
 
        list_for_each_entry(report,
                &hid->report_enum[HID_INPUT_REPORT].report_list, list)
@@ -464,48 +465,38 @@ static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
        }
 }
 
-static int i2c_hid_alloc_buffers(struct i2c_hid *ihid)
+static void i2c_hid_free_buffers(struct i2c_hid *ihid)
+{
+       kfree(ihid->inbuf);
+       kfree(ihid->argsbuf);
+       kfree(ihid->cmdbuf);
+       ihid->inbuf = NULL;
+       ihid->cmdbuf = NULL;
+       ihid->argsbuf = NULL;
+       ihid->bufsize = 0;
+}
+
+static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
 {
        /* the worst case is computed from the set_report command with a
         * reportID > 15 and the maximum report length */
        int args_len = sizeof(__u8) + /* optional ReportID byte */
                       sizeof(__u16) + /* data register */
                       sizeof(__u16) + /* size of the report */
-                      ihid->bufsize; /* report */
-
-       ihid->inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
-
-       if (!ihid->inbuf)
-               return -ENOMEM;
+                      report_size; /* report */
 
+       ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
        ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
-
-       if (!ihid->argsbuf) {
-               kfree(ihid->inbuf);
-               return -ENOMEM;
-       }
-
        ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
 
-       if (!ihid->cmdbuf) {
-               kfree(ihid->inbuf);
-               kfree(ihid->argsbuf);
-               ihid->inbuf = NULL;
-               ihid->argsbuf = NULL;
+       if (!ihid->inbuf || !ihid->argsbuf || !ihid->cmdbuf) {
+               i2c_hid_free_buffers(ihid);
                return -ENOMEM;
        }
 
-       return 0;
-}
+       ihid->bufsize = report_size;
 
-static void i2c_hid_free_buffers(struct i2c_hid *ihid)
-{
-       kfree(ihid->inbuf);
-       kfree(ihid->argsbuf);
-       kfree(ihid->cmdbuf);
-       ihid->inbuf = NULL;
-       ihid->cmdbuf = NULL;
-       ihid->argsbuf = NULL;
+       return 0;
 }
 
 static int i2c_hid_get_raw_report(struct hid_device *hid,
@@ -514,23 +505,31 @@ static int i2c_hid_get_raw_report(struct hid_device *hid,
 {
        struct i2c_client *client = hid->driver_data;
        struct i2c_hid *ihid = i2c_get_clientdata(client);
+       size_t ret_count, ask_count;
        int ret;
 
        if (report_type == HID_OUTPUT_REPORT)
                return -EINVAL;
 
-       if (count > ihid->bufsize)
-               count = ihid->bufsize;
+       /* +2 bytes to include the size of the reply in the query buffer */
+       ask_count = min(count + 2, (size_t)ihid->bufsize);
 
        ret = i2c_hid_get_report(client,
                        report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
-                       report_number, ihid->inbuf, count);
+                       report_number, ihid->inbuf, ask_count);
 
        if (ret < 0)
                return ret;
 
-       count = ihid->inbuf[0] | (ihid->inbuf[1] << 8);
+       ret_count = ihid->inbuf[0] | (ihid->inbuf[1] << 8);
 
+       if (ret_count <= 2)
+               return 0;
+
+       ret_count = min(ret_count, ask_count);
+
+       /* The query buffer contains the size, dropping it in the reply */
+       count = min(count, ret_count - 2);
        memcpy(buf, ihid->inbuf + 2, count);
 
        return count;
@@ -541,13 +540,24 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
 {
        struct i2c_client *client = hid->driver_data;
        int report_id = buf[0];
+       int ret;
 
        if (report_type == HID_INPUT_REPORT)
                return -EINVAL;
 
-       return i2c_hid_set_report(client,
+       if (report_id) {
+               buf++;
+               count--;
+       }
+
+       ret = i2c_hid_set_report(client,
                                report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
                                report_id, buf, count);
+
+       if (report_id && ret >= 0)
+               ret++; /* add report_id to the number of transfered bytes */
+
+       return ret;
 }
 
 static int i2c_hid_parse(struct hid_device *hid)
@@ -610,22 +620,19 @@ static int i2c_hid_start(struct hid_device *hid)
        struct i2c_client *client = hid->driver_data;
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        int ret;
-       int old_bufsize = ihid->bufsize;
+       unsigned int bufsize = HID_MIN_BUFFER_SIZE;
 
-       ihid->bufsize = HID_MIN_BUFFER_SIZE;
-       i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &ihid->bufsize);
-       i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &ihid->bufsize);
-       i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &ihid->bufsize);
+       i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
+       i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
+       i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
 
-       if (ihid->bufsize > old_bufsize || !ihid->inbuf || !ihid->cmdbuf) {
+       if (bufsize > ihid->bufsize) {
                i2c_hid_free_buffers(ihid);
 
-               ret = i2c_hid_alloc_buffers(ihid);
+               ret = i2c_hid_alloc_buffers(ihid, bufsize);
 
-               if (ret) {
-                       ihid->bufsize = old_bufsize;
+               if (ret)
                        return ret;
-               }
        }
 
        if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
@@ -648,17 +655,20 @@ static int i2c_hid_open(struct hid_device *hid)
 {
        struct i2c_client *client = hid->driver_data;
        struct i2c_hid *ihid = i2c_get_clientdata(client);
-       int ret;
+       int ret = 0;
 
+       mutex_lock(&i2c_hid_open_mut);
        if (!hid->open++) {
                ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
                if (ret) {
                        hid->open--;
-                       return -EIO;
+                       goto done;
                }
                set_bit(I2C_HID_STARTED, &ihid->flags);
        }
-       return 0;
+done:
+       mutex_unlock(&i2c_hid_open_mut);
+       return ret;
 }
 
 static void i2c_hid_close(struct hid_device *hid)
@@ -670,12 +680,14 @@ static void i2c_hid_close(struct hid_device *hid)
         * data acquistion due to a resumption we no longer
         * care about
         */
+       mutex_lock(&i2c_hid_open_mut);
        if (!--hid->open) {
                clear_bit(I2C_HID_STARTED, &ihid->flags);
 
                /* Save some power */
                i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
        }
+       mutex_unlock(&i2c_hid_open_mut);
 }
 
 static int i2c_hid_power(struct hid_device *hid, int lvl)
@@ -717,9 +729,7 @@ static int i2c_hid_hidinput_input_event(struct input_dev *dev,
                return -1;
        }
 
-       hid_set_field(field, offset, value);
-
-       return 0;
+       return hid_set_field(field, offset, value);
 }
 
 static struct hid_ll_driver i2c_hid_ll_driver = {
@@ -732,7 +742,7 @@ static struct hid_ll_driver i2c_hid_ll_driver = {
        .hidinput_input_event = i2c_hid_hidinput_input_event,
 };
 
-static int __devinit i2c_hid_init_irq(struct i2c_client *client)
+static int i2c_hid_init_irq(struct i2c_client *client)
 {
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        int ret;
@@ -743,20 +753,18 @@ static int __devinit i2c_hid_init_irq(struct i2c_client *client)
                        IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
                        client->name, ihid);
        if (ret < 0) {
-               dev_dbg(&client->dev,
+               dev_warn(&client->dev,
                        "Could not register for %s interrupt, irq = %d,"
                        " ret = %d\n",
-               client->name, client->irq, ret);
+                       client->name, client->irq, ret);
 
                return ret;
        }
 
-       ihid->irq = client->irq;
-
        return 0;
 }
 
-static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
+static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
 {
        struct i2c_client *client = ihid->client;
        struct i2c_hid_desc *hdesc = &ihid->hdesc;
@@ -772,13 +780,20 @@ static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
                        __func__, 4, ihid->hdesc_buffer);
 
        if (ret) {
-               dev_err(&client->dev, "HID_DESCR_LENGTH_CMD Fail (ret=%d)\n",
+               dev_err(&client->dev,
+                       "unable to fetch the size of HID descriptor (ret=%d)\n",
                        ret);
                return -ENODEV;
        }
 
        dsize = le16_to_cpu(hdesc->wHIDDescLength);
-       if (!dsize || dsize > HID_MAX_DESCRIPTOR_SIZE) {
+       /*
+        * the size of the HID descriptor should at least contain
+        * its size and the bcdVersion (4 bytes), and should not be greater
+        * than sizeof(struct i2c_hid_desc) as we directly fill this struct
+        * through i2c_hid_command.
+        */
+       if (dsize < 4 || dsize > sizeof(struct i2c_hid_desc)) {
                dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
                        dsize);
                return -ENODEV;
@@ -787,7 +802,7 @@ static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
        /* check bcdVersion == 1.0 */
        if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
                dev_err(&client->dev,
-                       "unexpected HID descriptor bcdVersion (0x%04x)\n",
+                       "unexpected HID descriptor bcdVersion (0x%04hx)\n",
                        le16_to_cpu(hdesc->bcdVersion));
                return -ENODEV;
        }
@@ -806,8 +821,8 @@ static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
        return 0;
 }
 
-static int __devinit i2c_hid_probe(struct i2c_client *client,
-               const struct i2c_device_id *dev_id)
+static int i2c_hid_probe(struct i2c_client *client,
+                        const struct i2c_device_id *dev_id)
 {
        int ret;
        struct i2c_hid *ihid;
@@ -844,8 +859,9 @@ static int __devinit i2c_hid_probe(struct i2c_client *client,
        /* we need to allocate the command buffer without knowing the maximum
         * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
         * real computation later. */
-       ihid->bufsize = HID_MIN_BUFFER_SIZE;
-       i2c_hid_alloc_buffers(ihid);
+       ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
+       if (ret < 0)
+               goto err;
 
        ret = i2c_hid_fetch_hid_descriptor(ihid);
        if (ret < 0)
@@ -858,7 +874,7 @@ static int __devinit i2c_hid_probe(struct i2c_client *client,
        hid = hid_allocate_device();
        if (IS_ERR(hid)) {
                ret = PTR_ERR(hid);
-               goto err;
+               goto err_irq;
        }
 
        ihid->hid = hid;
@@ -873,7 +889,7 @@ static int __devinit i2c_hid_probe(struct i2c_client *client,
        hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
        hid->product = le16_to_cpu(ihid->hdesc.wProductID);
 
-       snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
+       snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
                 client->name, hid->vendor, hid->product);
 
        ret = hid_add_device(hid);
@@ -888,28 +904,28 @@ static int __devinit i2c_hid_probe(struct i2c_client *client,
 err_mem_free:
        hid_destroy_device(hid);
 
-err:
-       if (ihid->irq)
-               free_irq(ihid->irq, ihid);
+err_irq:
+       free_irq(client->irq, ihid);
 
+err:
        i2c_hid_free_buffers(ihid);
        kfree(ihid);
        return ret;
 }
 
-static int __devexit i2c_hid_remove(struct i2c_client *client)
+static int i2c_hid_remove(struct i2c_client *client)
 {
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        struct hid_device *hid;
 
-       if (WARN_ON(!ihid))
-               return -1;
-
        hid = ihid->hid;
        hid_destroy_device(hid);
 
        free_irq(client->irq, ihid);
 
+       if (ihid->bufsize)
+               i2c_hid_free_buffers(ihid);
+
        kfree(ihid);
 
        return 0;
@@ -919,10 +935,9 @@ static int __devexit i2c_hid_remove(struct i2c_client *client)
 static int i2c_hid_suspend(struct device *dev)
 {
        struct i2c_client *client = to_i2c_client(dev);
-       struct i2c_hid *ihid = i2c_get_clientdata(client);
 
        if (device_may_wakeup(&client->dev))
-               enable_irq_wake(ihid->irq);
+               enable_irq_wake(client->irq);
 
        /* Save some power */
        i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
@@ -963,7 +978,7 @@ static struct i2c_driver i2c_hid_driver = {
        },
 
        .probe          = i2c_hid_probe,
-       .remove         = __devexit_p(i2c_hid_remove),
+       .remove         = i2c_hid_remove,
 
        .id_table       = i2c_hid_id_table,
 };