From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartosz Golaszewski Subject: [PATCH] eeprom: at24: don't use the default regmap locking Date: Sun, 3 Dec 2017 22:47:43 +0100 Message-ID: <20171203214743.15970-1-brgl@bgdev.pl> Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:40100 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752503AbdLCVrs (ORCPT ); Sun, 3 Dec 2017 16:47:48 -0500 Received: by mail-wm0-f65.google.com with SMTP id f206so4958344wmf.5 for ; Sun, 03 Dec 2017 13:47:47 -0800 (PST) Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Heiner Kallweit Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski We need to always wait for the last write to complete and we want the regmap to be protected from concurrent access during that wait. That makes using the regmap's default locking impossible and we're protecting it with an external mutex. Set an empty function as the callback for regmap's lock and unlock routines so that it doesn't allocate any internal resources for unnecessary locking. Signed-off-by: Bartosz Golaszewski --- This is a temporary solution - I'm working on a patch extending the regmap framework with locking policy options, which will allow users to manually lock & unlock regmaps if needed or disable locking at all. drivers/misc/eeprom/at24.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 625b00166117..34bc394a9c14 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -498,14 +498,23 @@ static unsigned int at24_get_offset_adj(u8 flags, unsigned int byte_len) } } +static void at24_regmap_lock_unlock_none(void *map) +{ + +} + static const struct regmap_config regmap_config_8 = { .reg_bits = 8, .val_bits = 8, + .lock = at24_regmap_lock_unlock_none, + .unlock = at24_regmap_lock_unlock_none, }; static const struct regmap_config regmap_config_16 = { .reg_bits = 16, .val_bits = 8, + .lock = at24_regmap_lock_unlock_none, + .unlock = at24_regmap_lock_unlock_none, }; static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) -- 2.15.1