From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: [PATCH v2 5/7] eeprom: at24: add regmap-based read functions Date: Thu, 16 Nov 2017 21:26:44 +0100 Message-ID: <055dce44-43fb-c90f-6e94-ca8035b16832@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:43523 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759041AbdKPU1X (ORCPT ); Thu, 16 Nov 2017 15:27:23 -0500 Received: by mail-wm0-f66.google.com with SMTP id x63so2620132wmf.2 for ; Thu, 16 Nov 2017 12:27:23 -0800 (PST) In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Bartosz Golaszewski Cc: "linux-i2c@vger.kernel.org" Add regmap-based read functions. Signed-off-by: Heiner Kallweit --- v2: - rebased --- drivers/misc/eeprom/at24.c | 58 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 57 insertions(+), 1 deletion(-) diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 28ea1a950..391e0d998 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -310,6 +310,59 @@ static ssize_t at24_eeprom_read_smbus(struct at24_data *at24, char *buf, return -ETIMEDOUT; } +static ssize_t at24_regmap_read(struct at24_data *at24, char *buf, + unsigned int offset, size_t count) +{ + unsigned long timeout, read_time; + struct regmap *regmap; + + regmap = at24_translate_offset(at24, &offset)->regmap; + + if (count > io_limit) + count = io_limit; + + if (at24->chip.flags & AT24_FLAG_MAC) + offset += 0x90; + + loop_until_timeout(timeout, read_time) + if (!regmap_bulk_read(regmap, offset, buf, count)) + return count; + + return -ETIMEDOUT; +} + +static ssize_t at24_regmap_read_serial(struct at24_data *at24, char *buf, + unsigned int offset, size_t count) +{ + unsigned long timeout, read_time; + struct regmap *regmap; + + regmap = at24_translate_offset(at24, &offset)->regmap; + + if (count > io_limit) + count = io_limit; + + if (at24->chip.flags & AT24_FLAG_ADDR16) + /* + * For 16 bit address pointers, the word address must contain + * a '10' sequence in bits 11 and 10 regardless of the + * intended position of the address pointer. + */ + offset |= BIT(11); + else + /* + * Otherwise the word address must begin with a '10' sequence, + * regardless of the intended address. + */ + offset |= BIT(7); + + loop_until_timeout(timeout, read_time) + if (!regmap_bulk_read(regmap, offset, buf, count)) + return count; + + return -ETIMEDOUT; +} + static ssize_t at24_eeprom_read_i2c(struct at24_data *at24, char *buf, unsigned int offset, size_t count) { @@ -512,7 +565,10 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) while (count) { int status; - status = at24->read_func(at24, buf, off, count); + if (at24->chip.flags & AT24_FLAG_SERIAL) + status = at24_regmap_read_serial(at24, buf, off, count); + else + status = at24_regmap_read(at24, buf, off, count); if (status < 0) { mutex_unlock(&at24->lock); pm_runtime_put(&client->dev); -- 2.15.0