From 9d8dc3e529a19e427fd379118acd132520935c5d Mon Sep 17 00:00:00 2001 From: Nick Dyer Date: Wed, 23 Jul 2014 12:49:04 -0700 Subject: [PATCH] Input: atmel_mxt_ts - implement T44 message handling maXTouch chips allow the reading of multiple messages in a single I2C transaction, which reduces bus overhead and improves performance/latency. The number of messages available to be read is given by the value in the T44 object which is located directly before the T5 object. Signed-off-by: Nick Dyer Acked-by: Benson Leung Acked-by: Yufeng Shen Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/atmel_mxt_ts.c | 191 +++++++++++++++++++---- 1 file changed, 159 insertions(+), 32 deletions(-) diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index 699de552a6d8ab..c6dfd0af636516 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -244,12 +244,15 @@ struct mxt_data { unsigned int max_y; bool in_bootloader; u16 mem_size; + u8 max_reportid; u32 config_crc; u32 info_crc; u8 bootloader_addr; u8 *msg_buf; u8 t6_status; bool update_input; + u8 last_message_count; + u8 num_touchids; /* Cached parameters from object table */ u16 T5_address; @@ -260,6 +263,7 @@ struct mxt_data { u8 T9_reportid_min; u8 T9_reportid_max; u8 T19_reportid; + u16 T44_address; /* for fw update in bootloader */ struct completion bl_completion; @@ -795,30 +799,142 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message) return 1; } -static int mxt_read_and_process_message(struct mxt_data *data) +static int mxt_read_and_process_messages(struct mxt_data *data, u8 count) { struct device *dev = &data->client->dev; int ret; + int i; + u8 num_valid = 0; + + /* Safety check for msg_buf */ + if (count > data->max_reportid) + return -EINVAL; + /* Process remaining messages if necessary */ ret = __mxt_read_reg(data->client, data->T5_address, - data->T5_msg_size, data->msg_buf); + data->T5_msg_size * count, data->msg_buf); if (ret) { - dev_err(dev, "Error %d reading message\n", ret); + dev_err(dev, "Failed to read %u messages (%d)\n", count, ret); return ret; } - return mxt_proc_message(data, data->msg_buf); + for (i = 0; i < count; i++) { + ret = mxt_proc_message(data, + data->msg_buf + data->T5_msg_size * i); + + if (ret == 1) + num_valid++; + } + + /* return number of messages read */ + return num_valid; } -static irqreturn_t mxt_process_messages_until_invalid(struct mxt_data *data) +static irqreturn_t mxt_process_messages_t44(struct mxt_data *data) { + struct device *dev = &data->client->dev; int ret; + u8 count, num_left; - do { - ret = mxt_read_and_process_message(data); + /* Read T44 and T5 together */ + ret = __mxt_read_reg(data->client, data->T44_address, + data->T5_msg_size + 1, data->msg_buf); + if (ret) { + dev_err(dev, "Failed to read T44 and T5 (%d)\n", ret); + return IRQ_NONE; + } + + count = data->msg_buf[0]; + + if (count == 0) { + dev_warn(dev, "Interrupt triggered but zero messages\n"); + return IRQ_NONE; + } else if (count > data->max_reportid) { + dev_err(dev, "T44 count %d exceeded max report id\n", count); + count = data->max_reportid; + } + + /* Process first message */ + ret = mxt_proc_message(data, data->msg_buf + 1); + if (ret < 0) { + dev_warn(dev, "Unexpected invalid message\n"); + return IRQ_NONE; + } + + num_left = count - 1; + + /* Process remaining messages if necessary */ + if (num_left) { + ret = mxt_read_and_process_messages(data, num_left); if (ret < 0) + goto end; + else if (ret != num_left) + dev_warn(dev, "Unexpected invalid message\n"); + } + +end: + if (data->update_input) { + mxt_input_sync(data); + data->update_input = false; + } + + return IRQ_HANDLED; +} + +static int mxt_process_messages_until_invalid(struct mxt_data *data) +{ + struct device *dev = &data->client->dev; + int count, read; + u8 tries = 2; + + count = data->max_reportid; + + /* Read messages until we force an invalid */ + do { + read = mxt_read_and_process_messages(data, count); + if (read < count) + return 0; + } while (--tries); + + if (data->update_input) { + mxt_input_sync(data); + data->update_input = false; + } + + dev_err(dev, "CHG pin isn't cleared\n"); + return -EBUSY; +} + +static irqreturn_t mxt_process_messages(struct mxt_data *data) +{ + int total_handled, num_handled; + u8 count = data->last_message_count; + + if (count < 1 || count > data->max_reportid) + count = 1; + + /* include final invalid message */ + total_handled = mxt_read_and_process_messages(data, count + 1); + if (total_handled < 0) + return IRQ_NONE; + /* if there were invalid messages, then we are done */ + else if (total_handled <= count) + goto update_count; + + /* keep reading two msgs until one is invalid or reportid limit */ + do { + num_handled = mxt_read_and_process_messages(data, 2); + if (num_handled < 0) return IRQ_NONE; - } while (ret > 0); + + total_handled += num_handled; + + if (num_handled < 2) + break; + } while (total_handled < data->num_touchids); + +update_count: + data->last_message_count = total_handled; if (data->update_input) { mxt_input_sync(data); @@ -841,7 +957,11 @@ static irqreturn_t mxt_interrupt(int irq, void *dev_id) if (!data->object_table) return IRQ_HANDLED; - return mxt_process_messages_until_invalid(data); + if (data->T44_address) { + return mxt_process_messages_t44(data); + } else { + return mxt_process_messages(data); + } } static int mxt_t6_command(struct mxt_data *data, u16 cmd_offset, @@ -1214,32 +1334,13 @@ static int mxt_update_cfg(struct mxt_data *data, const struct firmware *cfg) return ret; } -static int mxt_make_highchg(struct mxt_data *data) -{ - struct device *dev = &data->client->dev; - int count = 10; - int ret; - - /* Read messages until we force an invalid */ - do { - ret = mxt_read_and_process_message(data); - if (ret == 0) - return 0; - else if (ret < 0) - return ret; - } while (--count); - - dev_err(dev, "CHG pin isn't cleared\n"); - return -EBUSY; -} - static int mxt_acquire_irq(struct mxt_data *data) { int error; enable_irq(data->irq); - error = mxt_make_highchg(data); + error = mxt_process_messages_until_invalid(data); if (error) return error; @@ -1276,6 +1377,8 @@ static void mxt_free_object_table(struct mxt_data *data) data->T9_reportid_min = 0; data->T9_reportid_max = 0; data->T19_reportid = 0; + data->T44_address = 0; + data->max_reportid = 0; } static int mxt_get_object_table(struct mxt_data *data) @@ -1329,8 +1432,16 @@ static int mxt_get_object_table(struct mxt_data *data) switch (object->type) { case MXT_GEN_MESSAGE_T5: - /* CRC not enabled, therefore don't read last byte */ - data->T5_msg_size = mxt_obj_size(object) - 1; + 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); + } else { + /* CRC not enabled, so skip last byte */ + data->T5_msg_size = mxt_obj_size(object) - 1; + } data->T5_address = object->start_address; case MXT_GEN_COMMAND_T6: data->T6_reportid = min_id; @@ -1342,6 +1453,11 @@ static int mxt_get_object_table(struct mxt_data *data) case MXT_TOUCH_MULTI_T9: data->T9_reportid_min = min_id; data->T9_reportid_max = max_id; + data->num_touchids = object->num_report_ids + * mxt_obj_instances(object); + break; + case MXT_SPT_MESSAGECOUNT_T44: + data->T44_address = object->start_address; break; case MXT_SPT_GPIOPWM_T19: data->T19_reportid = min_id; @@ -1355,7 +1471,18 @@ static int mxt_get_object_table(struct mxt_data *data) data->mem_size = end_address + 1; } - data->msg_buf = kzalloc(data->T5_msg_size, GFP_KERNEL); + /* Store maximum reportid */ + data->max_reportid = reportid; + + /* 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; + } + + 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"); error = -ENOMEM;