| Message ID | 1370453866-16534-45-git-send-email-nick.dyer@itdev.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jun 5, 2013 at 1:37 PM, Nick Dyer <nick.dyer@itdev.co.uk> wrote: > By reading the information block and the object table into a contiguous region > of memory, we can verify the checksum at probe time. This means we verify that > we are indeed talking to a chip that supports object protocol correctly. We > also detect I2C comms problems much earlier, resulting in easier diagnosis. > > Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk> > Acked-by: Benson Leung <bleung@chromium.org> > --- > drivers/input/touchscreen/atmel_mxt_ts.c | 181 ++++++++++++++++++------------ > 1 file changed, 111 insertions(+), 70 deletions(-) > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > index bbfea7a..e0ff017 100644 > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > @@ -194,7 +194,8 @@ struct mxt_data { > char phys[64]; /* device physical location */ > 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; > @@ -365,12 +366,16 @@ static int mxt_lookup_bootloader_address(struct mxt_data *data, bool retry) > { > u8 appmode = data->client->addr; > u8 bootloader; > + u8 family_id = 0; > + > + if (data->info) > + family_id = data->info->family_id; > > 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; > } > @@ -610,7 +615,7 @@ 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; > @@ -1249,13 +1254,13 @@ static int mxt_check_reg_init(struct mxt_data *data) > 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"); > ret = -EINVAL; > goto release; > } > > - 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"); > ret = -EINVAL; > goto release; > @@ -1302,7 +1307,7 @@ static int mxt_check_reg_init(struct mxt_data *data) > > /* 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); > @@ -1510,24 +1515,12 @@ static int mxt_acquire_irq(struct mxt_data *data) > return 0; > } > > -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_object_table(struct mxt_data *data) > { > - kfree(data->object_table); > + kfree(data->raw_info_block); > data->object_table = NULL; > + data->info = NULL; > + data->raw_info_block = NULL; > kfree(data->msg_buf); > data->msg_buf = NULL; > data->enable_reporting = false; > @@ -1549,25 +1542,17 @@ 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 i2c_client *client = data->client; > - size_t table_size; > - int error; > int i; > u8 reportid; > u16 end_address; > > - table_size = data->info.object_num * sizeof(struct mxt_object); > - error = __mxt_read_reg(client, MXT_OBJECT_START, table_size, > - data->object_table); > - if (error) > - 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 = data->object_table + i; > u8 min_id, max_id; > > @@ -1591,7 +1576,7 @@ static int mxt_get_object_table(struct mxt_data *data) > > switch (object->type) { > case MXT_GEN_MESSAGE_T5: > - if (data->info.family_id == 0x80) { > + if (data->info->family_id == 0x80) { > /* On mXT224 read and discard unused CRC byte > * otherwise DMA reads are misaligned */ > data->T5_msg_size = mxt_obj_size(object); > @@ -1651,22 +1636,102 @@ 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"); > + 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 *buf; > + struct mxt_info *info; > + u32 calculated_crc; > + u8 *crc_ptr; > + > + /* If info block already allocated, free it */ > + if (data->raw_info_block != NULL) > + mxt_free_object_table(data); > + > + /* Read 7-byte ID information block starting at address 0 */ > + size = sizeof(struct mxt_info); > + buf = kzalloc(size, GFP_KERNEL); > + if (!buf) { > + dev_err(&client->dev, "Failed to allocate memory\n"); > + return -ENOMEM; > + } > + > + error = __mxt_read_reg(client, 0, size, buf); > + if (error) > + goto err_free_mem; > + > + /* Resize buffer to give space for rest of info block */ > + info = (struct mxt_info *)buf; > + size += (info->object_num * sizeof(struct mxt_object)) > + + MXT_INFO_CHECKSUM_SIZE; > + > + buf = krealloc(buf, size, GFP_KERNEL); > + if (!buf) { > + dev_err(&client->dev, "Failed to allocate memory\n"); > error = -ENOMEM; > - goto free_object_table; > + goto err_free_mem; > + } > + > + /* Read rest of info block */ > + error = __mxt_read_reg(client, MXT_OBJECT_START, > + size - MXT_OBJECT_START, > + buf + MXT_OBJECT_START); > + if (error) > + goto err_free_mem; > + > + /* Extract & calculate checksum */ > + crc_ptr = 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(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 */ > + 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", > + data->info_crc, calculated_crc); > + return -EIO; > + } > + > + /* Save pointers in device data structure */ > + data->raw_info_block = buf; > + data->info = (struct mxt_info *)buf; > + data->object_table = (struct mxt_object *)(buf + MXT_OBJECT_START); > + > + dev_info(&client->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); > + Use data->info->XXX here, info was pointing to buf which could have changed after krealloc. > + /* Parse object table information */ > + error = mxt_parse_object_table(data); > + if (error) { > + dev_err(&client->dev, "Error %d reading object table\n", error); > + mxt_free_object_table(data); > + return error; > } > > return 0; > > -free_object_table: > - mxt_free_object_table(data); > +err_free_mem: > + kfree(buf); > return error; > } > > @@ -1721,13 +1786,12 @@ static int mxt_read_t9_resolution(struct mxt_data *data) > static int mxt_initialize(struct mxt_data *data) > { > struct i2c_client *client = data->client; > - struct mxt_info *info = &data->info; > int error; > bool alt_bootloader_addr = false; > bool retry = false; > > retry_info: > - error = mxt_get_info(data); > + error = mxt_read_info_block(data); > if (error) { > retry_bootloader: > error = mxt_probe_bootloader(data, alt_bootloader_addr); > @@ -1759,21 +1823,6 @@ retry_bootloader: > } > } > > - data->object_table = kcalloc(info->object_num, > - sizeof(struct mxt_object), > - GFP_KERNEL); > - if (!data->object_table) { > - dev_err(&client->dev, "Failed to allocate memory\n"); > - return -ENOMEM; > - } > - > - /* Get object table information */ > - error = mxt_get_object_table(data); > - if (error) { > - dev_err(&client->dev, "Error %d reading object table\n", error); > - goto err_free_object_table; > - } > - > error = mxt_acquire_irq(data); > if (error) > goto err_free_object_table; > @@ -1792,17 +1841,6 @@ retry_bootloader: > goto err_free_object_table; > } > > - error = mxt_read_t9_resolution(data); > - if (error) { > - dev_err(&client->dev, "Failed to initialize T9 resolution\n"); > - goto err_free_object_table; > - } > - > - dev_info(&client->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); > - > data->enable_reporting = true; > > return 0; > @@ -1817,9 +1855,9 @@ 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; > return scnprintf(buf, PAGE_SIZE, "%u.%u.%02X\n", > - info->version >> 4, info->version & 0xf, info->build); > + data->info->version >> 4, data->info->version & 0xf, > + data->info->build); > } > > /* Hardware Version is returned as FamilyID.VariantID */ > @@ -1827,9 +1865,8 @@ 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; > return scnprintf(buf, PAGE_SIZE, "%u.%u\n", > - info->family_id, info->variant_id); > + data->info->family_id, data->info->variant_id); > } > > static ssize_t mxt_show_instance(char *buf, int count, > @@ -1866,7 +1903,7 @@ 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)) > @@ -2211,6 +2248,10 @@ static int mxt_initialize_t9_input_device(struct mxt_data *data) > unsigned int mt_flags = 0; > int i; > > + error = mxt_read_t9_resolution(data); > + if (error) > + dev_warn(dev, "Failed to initialize T9 resolution\n"); > + > input_dev = input_allocate_device(); > if (!input_dev) { > dev_err(dev, "Failed to allocate memory\n"); > -- > 1.7.10.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-input" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Yufeng Shen wrote: >> + dev_info(&client->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); >> + > > Use data->info->XXX here, info was pointing to buf which could have > changed after krealloc. Thank you, that's a really good spot. Caused when I merged the dev_info line into that function. It actually explains a report I had about getting junk in this output but the info_crc check succeeding, hadn't had time to investigate yet. I will fix. -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index bbfea7a..e0ff017 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -194,7 +194,8 @@ struct mxt_data { char phys[64]; /* device physical location */ 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; @@ -365,12 +366,16 @@ static int mxt_lookup_bootloader_address(struct mxt_data *data, bool retry) { u8 appmode = data->client->addr; u8 bootloader; + u8 family_id = 0; + + if (data->info) + family_id = data->info->family_id; 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; } @@ -610,7 +615,7 @@ 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; @@ -1249,13 +1254,13 @@ static int mxt_check_reg_init(struct mxt_data *data) 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"); ret = -EINVAL; goto release; } - 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"); ret = -EINVAL; goto release; @@ -1302,7 +1307,7 @@ static int mxt_check_reg_init(struct mxt_data *data) /* 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); @@ -1510,24 +1515,12 @@ static int mxt_acquire_irq(struct mxt_data *data) return 0; } -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_object_table(struct mxt_data *data) { - kfree(data->object_table); + kfree(data->raw_info_block); data->object_table = NULL; + data->info = NULL; + data->raw_info_block = NULL; kfree(data->msg_buf); data->msg_buf = NULL; data->enable_reporting = false; @@ -1549,25 +1542,17 @@ 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 i2c_client *client = data->client; - size_t table_size; - int error; int i; u8 reportid; u16 end_address; - table_size = data->info.object_num * sizeof(struct mxt_object); - error = __mxt_read_reg(client, MXT_OBJECT_START, table_size, - data->object_table); - if (error) - 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 = data->object_table + i; u8 min_id, max_id; @@ -1591,7 +1576,7 @@ static int mxt_get_object_table(struct mxt_data *data) switch (object->type) { case MXT_GEN_MESSAGE_T5: - if (data->info.family_id == 0x80) { + if (data->info->family_id == 0x80) { /* On mXT224 read and discard unused CRC byte * otherwise DMA reads are misaligned */ data->T5_msg_size = mxt_obj_size(object); @@ -1651,22 +1636,102 @@ 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"); + 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 *buf; + struct mxt_info *info; + u32 calculated_crc; + u8 *crc_ptr; + + /* If info block already allocated, free it */ + if (data->raw_info_block != NULL) + mxt_free_object_table(data); + + /* Read 7-byte ID information block starting at address 0 */ + size = sizeof(struct mxt_info); + buf = kzalloc(size, GFP_KERNEL); + if (!buf) { + dev_err(&client->dev, "Failed to allocate memory\n"); + return -ENOMEM; + } + + error = __mxt_read_reg(client, 0, size, buf); + if (error) + goto err_free_mem; + + /* Resize buffer to give space for rest of info block */ + info = (struct mxt_info *)buf; + size += (info->object_num * sizeof(struct mxt_object)) + + MXT_INFO_CHECKSUM_SIZE; + + buf = krealloc(buf, size, GFP_KERNEL); + if (!buf) { + dev_err(&client->dev, "Failed to allocate memory\n"); error = -ENOMEM; - goto free_object_table; + goto err_free_mem; + } + + /* Read rest of info block */ + error = __mxt_read_reg(client, MXT_OBJECT_START, + size - MXT_OBJECT_START, + buf + MXT_OBJECT_START); + if (error) + goto err_free_mem; + + /* Extract & calculate checksum */ + crc_ptr = 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(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 */ + 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", + data->info_crc, calculated_crc); + return -EIO; + } + + /* Save pointers in device data structure */ + data->raw_info_block = buf; + data->info = (struct mxt_info *)buf; + data->object_table = (struct mxt_object *)(buf + MXT_OBJECT_START); + + dev_info(&client->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); + + /* Parse object table information */ + error = mxt_parse_object_table(data); + if (error) { + dev_err(&client->dev, "Error %d reading object table\n", error); + mxt_free_object_table(data); + return error; } return 0; -free_object_table: - mxt_free_object_table(data); +err_free_mem: + kfree(buf); return error; } @@ -1721,13 +1786,12 @@ static int mxt_read_t9_resolution(struct mxt_data *data) static int mxt_initialize(struct mxt_data *data) { struct i2c_client *client = data->client; - struct mxt_info *info = &data->info; int error; bool alt_bootloader_addr = false; bool retry = false; retry_info: - error = mxt_get_info(data); + error = mxt_read_info_block(data); if (error) { retry_bootloader: error = mxt_probe_bootloader(data, alt_bootloader_addr); @@ -1759,21 +1823,6 @@ retry_bootloader: } } - data->object_table = kcalloc(info->object_num, - sizeof(struct mxt_object), - GFP_KERNEL); - if (!data->object_table) { - dev_err(&client->dev, "Failed to allocate memory\n"); - return -ENOMEM; - } - - /* Get object table information */ - error = mxt_get_object_table(data); - if (error) { - dev_err(&client->dev, "Error %d reading object table\n", error); - goto err_free_object_table; - } - error = mxt_acquire_irq(data); if (error) goto err_free_object_table; @@ -1792,17 +1841,6 @@ retry_bootloader: goto err_free_object_table; } - error = mxt_read_t9_resolution(data); - if (error) { - dev_err(&client->dev, "Failed to initialize T9 resolution\n"); - goto err_free_object_table; - } - - dev_info(&client->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); - data->enable_reporting = true; return 0; @@ -1817,9 +1855,9 @@ 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; return scnprintf(buf, PAGE_SIZE, "%u.%u.%02X\n", - info->version >> 4, info->version & 0xf, info->build); + data->info->version >> 4, data->info->version & 0xf, + data->info->build); } /* Hardware Version is returned as FamilyID.VariantID */ @@ -1827,9 +1865,8 @@ 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; return scnprintf(buf, PAGE_SIZE, "%u.%u\n", - info->family_id, info->variant_id); + data->info->family_id, data->info->variant_id); } static ssize_t mxt_show_instance(char *buf, int count, @@ -1866,7 +1903,7 @@ 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)) @@ -2211,6 +2248,10 @@ static int mxt_initialize_t9_input_device(struct mxt_data *data) unsigned int mt_flags = 0; int i; + error = mxt_read_t9_resolution(data); + if (error) + dev_warn(dev, "Failed to initialize T9 resolution\n"); + input_dev = input_allocate_device(); if (!input_dev) { dev_err(dev, "Failed to allocate memory\n");