Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752278AbdH3RFn (ORCPT ); Wed, 30 Aug 2017 13:05:43 -0400 Received: from mga11.intel.com ([192.55.52.93]:48541 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752087AbdH3RFl (ORCPT ); Wed, 30 Aug 2017 13:05:41 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.41,449,1498546800"; d="scan'208";a="124090725" From: Divagar Mohandass To: robh+dt@kernel.org, mark.rutland@arm.com, wsa@the-dreams.de, sakari.ailus@iki.fi Cc: devicetree@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, rajmohan.mani@intel.com, Divagar Mohandass Subject: [PATCH v4 3/3] eeprom: at24: enable runtime pm support Date: Wed, 30 Aug 2017 22:35:40 +0530 Message-Id: <1504112740-14072-4-git-send-email-divagar.mohandass@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1504112740-14072-1-git-send-email-divagar.mohandass@intel.com> References: <1504112740-14072-1-git-send-email-divagar.mohandass@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3820 Lines: 136 Currently the device is kept in D0, there is an opportunity to save power by enabling runtime pm. Device can be daisy chained from PMIC and we can't rely on I2C core for auto resume/suspend. Driver will decide when to resume/suspend. Signed-off-by: Divagar Mohandass --- drivers/misc/eeprom/at24.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 2199c42..65a7d83 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -24,6 +24,7 @@ #include #include #include +#include /* * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable. @@ -501,11 +502,21 @@ static ssize_t at24_eeprom_write_i2c(struct at24_data *at24, const char *buf, static int at24_read(void *priv, unsigned int off, void *val, size_t count) { struct at24_data *at24 = priv; + struct i2c_client *client; char *buf = val; + int ret; if (unlikely(!count)) return count; + client = at24_translate_offset(at24, &off); + + ret = pm_runtime_get_sync(&client->dev); + if (ret < 0) { + pm_runtime_put_noidle(&client->dev); + return ret; + } + /* * Read data from chip, protecting against concurrent updates * from this host, but not from other I2C masters. @@ -518,6 +529,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) status = at24->read_func(at24, buf, off, count); if (status < 0) { mutex_unlock(&at24->lock); + pm_runtime_put(&client->dev); return status; } buf += status; @@ -527,17 +539,29 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) mutex_unlock(&at24->lock); + pm_runtime_put(&client->dev); + return 0; } static int at24_write(void *priv, unsigned int off, void *val, size_t count) { struct at24_data *at24 = priv; + struct i2c_client *client; char *buf = val; + int ret; if (unlikely(!count)) return -EINVAL; + client = at24_translate_offset(at24, &off); + + ret = pm_runtime_get_sync(&client->dev); + if (ret < 0) { + pm_runtime_put_noidle(&client->dev); + return ret; + } + /* * Write data to chip, protecting against concurrent updates * from this host, but not from other I2C masters. @@ -550,6 +574,7 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) status = at24->write_func(at24, buf, off, count); if (status < 0) { mutex_unlock(&at24->lock); + pm_runtime_put(&client->dev); return status; } buf += status; @@ -559,6 +584,8 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) mutex_unlock(&at24->lock); + pm_runtime_put(&client->dev); + return 0; } @@ -743,6 +770,14 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) i2c_set_clientdata(client, at24); + /* enable runtime pm */ + pm_runtime_get_noresume(&client->dev); + err = pm_runtime_set_active(&client->dev); + if (err < 0) + goto err_clients; + + pm_runtime_enable(&client->dev); + /* * Perform a one-byte test read to verify that the * chip is functional. @@ -753,6 +788,8 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) goto err_clients; } + pm_runtime_put(&client->dev); + at24->nvmem_config.name = dev_name(&client->dev); at24->nvmem_config.dev = &client->dev; at24->nvmem_config.read_only = !writable; @@ -810,6 +847,9 @@ static int at24_remove(struct i2c_client *client) for (i = 1; i < at24->num_addresses; i++) i2c_unregister_device(at24->client[i]); + pm_runtime_disable(&client->dev); + pm_runtime_set_suspended(&client->dev); + return 0; } -- 1.9.1