1 files changed, 110 insertions, 76 deletions

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 429b694405c7..fc149ea64be7 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -275,7 +275,8 @@ struct mxt_data {
         char phys[64];          /* device physical location */
         const struct mxt_platform_data *pdata;
         struct mxt_object *object_table;
-        struct mxt_info info;
+        struct mxt_info *info;
+        void *raw_info_block;
         unsigned int irq;
         unsigned int max_x;
         unsigned int max_y;
@@ -450,12 +451,13 @@ static int mxt_lookup_bootloader_address(struct mxt_data *data, bool retry)
 {
         u8 appmode = data->client->addr;
         u8 bootloader;
+        u8 family_id = data->info ? data->info->family_id : 0;
 
         switch (appmode) {
         case 0x4a:
         case 0x4b:
                 /* Chips after 1664S use different scheme */
-                if (retry || data->info.family_id >= 0xa2) {
+                if (retry || family_id >= 0xa2) {
                         bootloader = appmode - 0x24;
                         break;
                 }
@@ -682,7 +684,7 @@ mxt_get_object(struct mxt_data *data, u8 type)
         struct mxt_object *object;
         int i;
 
-        for (i = 0; i < data->info.object_num; i++) {
+        for (i = 0; i < data->info->object_num; i++) {
                 object = data->object_table + i;
                 if (object->type == type)
                         return object;
@@ -1453,12 +1455,12 @@ static int mxt_update_cfg(struct mxt_data *data, const struct firmware *cfg)
                 data_pos += offset;
         }
 
-        if (cfg_info.family_id != data->info.family_id) {
+        if (cfg_info.family_id != data->info->family_id) {
                 dev_err(dev, "Family ID mismatch!\n");
                 return -EINVAL;
         }
 
-        if (cfg_info.variant_id != data->info.variant_id) {
+        if (cfg_info.variant_id != data->info->variant_id) {
                 dev_err(dev, "Variant ID mismatch!\n");
                 return -EINVAL;
         }
@@ -1503,7 +1505,7 @@ static int mxt_update_cfg(struct mxt_data *data, const struct firmware *cfg)
 
         /* Malloc memory to store configuration */
         cfg_start_ofs = MXT_OBJECT_START +
-                        data->info.object_num * sizeof(struct mxt_object) +
+                        data->info->object_num * sizeof(struct mxt_object) +
                         MXT_INFO_CHECKSUM_SIZE;
         config_mem_size = data->mem_size - cfg_start_ofs;
         config_mem = kzalloc(config_mem_size, GFP_KERNEL);
@@ -1554,20 +1556,6 @@ release_mem:
         return ret;
 }
 
-static int mxt_get_info(struct mxt_data *data)
-{
-        struct i2c_client *client = data->client;
-        struct mxt_info *info = &data->info;
-        int error;
-
-        /* Read 7-byte info block starting at address 0 */
-        error = __mxt_read_reg(client, 0, sizeof(*info), info);
-        if (error)
-                return error;
-
-        return 0;
-}
-
 static void mxt_free_input_device(struct mxt_data *data)
 {
         if (data->input_dev) {
@@ -1582,9 +1570,10 @@ static void mxt_free_object_table(struct mxt_data *data)
         video_unregister_device(&data->dbg.vdev);
         v4l2_device_unregister(&data->dbg.v4l2);
 #endif
-
-        kfree(data->object_table);
         data->object_table = NULL;
+        data->info = NULL;
+        kfree(data->raw_info_block);
+        data->raw_info_block = NULL;
         kfree(data->msg_buf);
         data->msg_buf = NULL;
         data->T5_address = 0;
@@ -1600,34 +1589,18 @@ static void mxt_free_object_table(struct mxt_data *data)
         data->max_reportid = 0;
 }
 
-static int mxt_get_object_table(struct mxt_data *data)
+static int mxt_parse_object_table(struct mxt_data *data,
+                                  struct mxt_object *object_table)
 {
         struct i2c_client *client = data->client;
-        size_t table_size;
-        struct mxt_object *object_table;
-        int error;
         int i;
         u8 reportid;
         u16 end_address;
 
-        table_size = data->info.object_num * sizeof(struct mxt_object);
-        object_table = kzalloc(table_size, GFP_KERNEL);
-        if (!object_table) {
-                dev_err(&data->client->dev, "Failed to allocate memory\n");
-                return -ENOMEM;
-        }
-
-        error = __mxt_read_reg(client, MXT_OBJECT_START, table_size,
-                        object_table);
-        if (error) {
-                kfree(object_table);
-                return error;
-        }
-
         /* Valid Report IDs start counting from 1 */
         reportid = 1;
         data->mem_size = 0;
-        for (i = 0; i < data->info.object_num; i++) {
+        for (i = 0; i < data->info->object_num; i++) {
                 struct mxt_object *object = object_table + i;
                 u8 min_id, max_id;
 
@@ -1651,8 +1624,8 @@ static int mxt_get_object_table(struct mxt_data *data)
 
                 switch (object->type) {
                 case MXT_GEN_MESSAGE_T5:
-                        if (data->info.family_id == 0x80 &&
-                            data->info.version < 0x20) {
+                        if (data->info->family_id == 0x80 &&
+                            data->info->version < 0x20) {
                                 /*
                                  * On mXT224 firmware versions prior to V2.0
                                  * read and discard unused CRC byte otherwise
@@ -1707,24 +1680,102 @@ static int mxt_get_object_table(struct mxt_data *data)
         /* If T44 exists, T5 position has to be directly after */
         if (data->T44_address && (data->T5_address != data->T44_address + 1)) {
                 dev_err(&client->dev, "Invalid T44 position\n");
-                error = -EINVAL;
-                goto free_object_table;
+                return -EINVAL;
         }
 
         data->msg_buf = kcalloc(data->max_reportid,
                                 data->T5_msg_size, GFP_KERNEL);
-        if (!data->msg_buf) {
-                dev_err(&client->dev, "Failed to allocate message buffer\n");
+        if (!data->msg_buf)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int mxt_read_info_block(struct mxt_data *data)
+{
+        struct i2c_client *client = data->client;
+        int error;
+        size_t size;
+        void *id_buf, *buf;
+        uint8_t num_objects;
+        u32 calculated_crc;
+        u8 *crc_ptr;
+
+        /* If info block already allocated, free it */
+        if (data->raw_info_block)
+                mxt_free_object_table(data);
+
+        /* Read 7-byte ID information block starting at address 0 */
+        size = sizeof(struct mxt_info);
+        id_buf = kzalloc(size, GFP_KERNEL);
+        if (!id_buf)
+                return -ENOMEM;
+
+        error = __mxt_read_reg(client, 0, size, id_buf);
+        if (error)
+                goto err_free_mem;
+
+        /* Resize buffer to give space for rest of info block */
+        num_objects = ((struct mxt_info *)id_buf)->object_num;
+        size += (num_objects * sizeof(struct mxt_object))
+                + MXT_INFO_CHECKSUM_SIZE;
+
+        buf = krealloc(id_buf, size, GFP_KERNEL);
+        if (!buf) {
                 error = -ENOMEM;
-                goto free_object_table;
+                goto err_free_mem;
+        }
+        id_buf = buf;
+
+        /* Read rest of info block */
+        error = __mxt_read_reg(client, MXT_OBJECT_START,
+                               size - MXT_OBJECT_START,
+                               id_buf + MXT_OBJECT_START);
+        if (error)
+                goto err_free_mem;
+
+        /* Extract & calculate checksum */
+        crc_ptr = id_buf + size - MXT_INFO_CHECKSUM_SIZE;
+        data->info_crc = crc_ptr[0] | (crc_ptr[1] << 8) | (crc_ptr[2] << 16);
+
+        calculated_crc = mxt_calculate_crc(id_buf, 0,
+                                           size - MXT_INFO_CHECKSUM_SIZE);
+
+        /*
+         * CRC mismatch can be caused by data corruption due to I2C comms
+         * issue or else device is not using Object Based Protocol (eg i2c-hid)
+         */
+        if ((data->info_crc == 0) || (data->info_crc != calculated_crc)) {
+                dev_err(&client->dev,
+                        "Info Block CRC error calculated=0x%06X read=0x%06X\n",
+                        calculated_crc, data->info_crc);
+                error = -EIO;
+                goto err_free_mem;
+        }
+
+        data->raw_info_block = id_buf;
+        data->info = (struct mxt_info *)id_buf;
+
+        dev_info(&client->dev,
+                 "Family: %u Variant: %u Firmware V%u.%u.%02X Objects: %u\n",
+                 data->info->family_id, data->info->variant_id,
+                 data->info->version >> 4, data->info->version & 0xf,
+                 data->info->build, data->info->object_num);
+
+        /* Parse object table information */
+        error = mxt_parse_object_table(data, id_buf + MXT_OBJECT_START);
+        if (error) {
+                dev_err(&client->dev, "Error %d parsing object table\n", error);
+                mxt_free_object_table(data);
+                goto err_free_mem;
         }
 
-        data->object_table = object_table;
+        data->object_table = (struct mxt_object *)(id_buf + MXT_OBJECT_START);
 
         return 0;
 
-free_object_table:
-        mxt_free_object_table(data);
+err_free_mem:
+        kfree(id_buf);
         return error;
 }
 
@@ -2039,7 +2090,7 @@ static int mxt_initialize(struct mxt_data *data)
         int error;
 
         while (1) {
-                error = mxt_get_info(data);
+                error = mxt_read_info_block(data);
                 if (!error)
                         break;
 
@@ -2070,16 +2121,9 @@ static int mxt_initialize(struct mxt_data *data)
                 msleep(MXT_FW_RESET_TIME);
         }
 
-        /* Get object table information */
-        error = mxt_get_object_table(data);
-        if (error) {
-                dev_err(&client->dev, "Error %d reading object table\n", error);
-                return error;
-        }
-
         error = mxt_acquire_irq(data);
         if (error)
-                goto err_free_object_table;
+                return error;
 
         error = request_firmware_nowait(THIS_MODULE, true, MXT_CFG_NAME,
                                         &client->dev, GFP_KERNEL, data,
@@ -2087,14 +2131,10 @@ static int mxt_initialize(struct mxt_data *data)
         if (error) {
                 dev_err(&client->dev, "Failed to invoke firmware loader: %d\n",
                         error);
-                goto err_free_object_table;
+                return error;
         }
 
         return 0;
-
-err_free_object_table:
-        mxt_free_object_table(data);
-        return error;
 }
 
 static int mxt_set_t7_power_cfg(struct mxt_data *data, u8 sleep)
@@ -2155,7 +2195,7 @@ recheck:
 static u16 mxt_get_debug_value(struct mxt_data *data, unsigned int x,
                                unsigned int y)
 {
-        struct mxt_info *info = &data->info;
+        struct mxt_info *info = data->info;
         struct mxt_dbg *dbg = &data->dbg;
         unsigned int ofs, page;
         unsigned int col = 0;
@@ -2483,7 +2523,7 @@ static const struct video_device mxt_video_device = {
 
 static void mxt_debug_init(struct mxt_data *data)
 {
-        struct mxt_info *info = &data->info;
+        struct mxt_info *info = data->info;
         struct mxt_dbg *dbg = &data->dbg;
         struct mxt_object *object;
         int error;
@@ -2569,7 +2609,6 @@ static int mxt_configure_objects(struct mxt_data *data,
                                  const struct firmware *cfg)
 {
         struct device *dev = &data->client->dev;
-        struct mxt_info *info = &data->info;
         int error;
 
         error = mxt_init_t7_power_cfg(data);
@@ -2594,11 +2633,6 @@ static int mxt_configure_objects(struct mxt_data *data,
 
         mxt_debug_init(data);
 
-        dev_info(dev,
-                 "Family: %u Variant: %u Firmware V%u.%u.%02X Objects: %u\n",
-                 info->family_id, info->variant_id, info->version >> 4,
-                 info->version & 0xf, info->build, info->object_num);
-
         return 0;
 }
 
@@ -2607,7 +2641,7 @@ static ssize_t mxt_fw_version_show(struct device *dev,
                                    struct device_attribute *attr, char *buf)
 {
         struct mxt_data *data = dev_get_drvdata(dev);
-        struct mxt_info *info = &data->info;
+        struct mxt_info *info = data->info;
         return scnprintf(buf, PAGE_SIZE, "%u.%u.%02X\n",
                          info->version >> 4, info->version & 0xf, info->build);
 }
@@ -2617,7 +2651,7 @@ static ssize_t mxt_hw_version_show(struct device *dev,
                                    struct device_attribute *attr, char *buf)
 {
         struct mxt_data *data = dev_get_drvdata(dev);
-        struct mxt_info *info = &data->info;
+        struct mxt_info *info = data->info;
         return scnprintf(buf, PAGE_SIZE, "%u.%u\n",
                          info->family_id, info->variant_id);
 }
@@ -2656,7 +2690,7 @@ static ssize_t mxt_object_show(struct device *dev,
                 return -ENOMEM;
 
         error = 0;
-        for (i = 0; i < data->info.object_num; i++) {
+        for (i = 0; i < data->info->object_num; i++) {
                 object = data->object_table + i;
 
                 if (!mxt_object_readable(object->type))