linux-toradex.git/drivers/input/touchscreen/raydium_i2c_ts.c, branch v5.10-rc4

Input: raydium_i2c_ts - use single i2c_transfer transaction when using RM_CMD_BANK_SWITCH

2020-09-14T06:32:58+00:00

On an AMD chromebook, where the same I2C bus is shared by both Raydium
touchscreen and a trackpad device, it is observed that interleaving of
I2C messages when `raydium_i2c_read_message()` is called leads to the
Raydium touch IC reporting incorrect information. This is the sequence
that was observed to result in the above issue:

* I2C write to Raydium device for RM_CMD_BANK_SWITCH
* I2C write to trackpad device
* I2C read from trackpad device
* I2C write to Raydium device for setting address
* I2C read from Raydium device >>>> This provides incorrect
  information

This change adds a new helper function `raydium_i2c_xfer()` that
performs I2C transactions to the Raydium device. It uses the register
address to decide if RM_CMD_BANK_SWITCH header needs to be sent to the
device (i.e. if register address is greater than 255, then bank switch
header is sent before the rest of the transaction). Additionally, it
ensures that all the I2C operations performed as part of
`raydium_i2c_xfer()` are done as a single i2c_transfer. This
guarantees that no other transactions are initiated to any other
device on the same bus in between. Additionally,
`raydium_i2c_{send|read}*` functions are refactored to use this new
helper function.

Verified with the patch across multiple reboots (>100) that the
information reported by the Raydium  touchscreen device during probe
is correct.

Signed-off-by: Furquan Shaikh 
Link: https://lore.kernel.org/r/20200821024006.3399663-1-furquan@google.com
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - fix error codes in raydium_i2c_boot_trigger()

2020-03-06T22:37:56+00:00

These functions are supposed to return negative error codes but instead
it returns true on failure and false on success.  The error codes are
eventually propagated back to user space.

Fixes: 48a2b783483b ("Input: add Raydium I2C touchscreen driver")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20200303101306.4potflz7na2nn3od@kili.mountain
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284

2019-06-05T15:36:37+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Alexios Zavras 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman

Input: raydium_i2c_ts - use true and false for boolean values

2018-08-08T18:23:26+00:00

Return statements in functions returning bool should use true or false
instead of an integer value.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - include hardware version in firmware name

2018-01-05T17:28:39+00:00

Add hardware version to the firmware file name to handle scenarios where
single system image supports variety of devices.

Signed-off-by: Jeffrey Lin 
Patchwork-Id: 10127677
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - use managed devm_device_add_group

2017-09-29T23:51:04+00:00

Commit 57b8ff070f98 ("driver core: add devm_device_add_group() and
friends") has added the managed version for creating sysfs group files.

Use devm_device_add_group instead of sysfs_create_group and remove the
action that cleans the sysfs file when exiting the driver.

Signed-off-by: Andi Shyti 
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - constify attribute_group structures

2017-07-12T21:19:29+00:00

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by  work with const
attribute_group. So mark the non-const structs as const.

File size before:
   text	   data	    bss	    dec	    hex	filename
   7801	    560	      0	   8361	   20a9	drivers/input/touchscreen/raydium_i2c_ts.o

File size After adding 'const':
   text	   data	    bss	    dec	    hex	filename
   7849	    496	      0	   8345	   2099	drivers/input/touchscreen/raydium_i2c_ts.o

Signed-off-by: Arvind Yadav 
Signed-off-by: Dmitry Torokhov

Input: touchscreen - drop unnecessary calls to input_set_drvdata

2017-01-23T01:22:31+00:00

Since there is no call to dev_get_drvdata() or input_get_drvdata(),
the call to input_set_drvdata() is unnecessary and can be dropped.

Signed-off-by: Guenter Roeck 
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - fix spelling mistake in dev_err message

2016-11-17T01:25:02+00:00

Trivial fix to spelling mistake "failied" to "failed" in
dev_err message.

Signed-off-by: Colin Ian King 
Signed-off-by: Dmitry Torokhov

Input: raydium_i2c_ts - check CRC of incoming packets

2016-07-14T00:27:24+00:00

Check CRC of incoming touch packets to ensure that we do not operate on
corrupted data.

Signed-off-by: Jeffrey Lin 
Signed-off-by: Dmitry Torokhov