Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752646AbdFNV7z (ORCPT ); Wed, 14 Jun 2017 17:59:55 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:33379 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751600AbdFNV7y (ORCPT ); Wed, 14 Jun 2017 17:59:54 -0400 From: Jaghathiswari Rankappagounder Natarajan To: zbr@ioremap.net, linux-kernel@vger.kernel.org, linux@roeck-us.net, jdelvare@suse.com, linux-hwmon@vger.kernel.org Cc: Jaghathiswari Rankappagounder Natarajan Subject: [PATCH linux v1 2/3] drivers: w1: refactor w1_slave_show to make the temp reading functionality separate Date: Wed, 14 Jun 2017 14:59:43 -0700 Message-Id: <20170614215944.24984-3-jaghu@google.com> X-Mailer: git-send-email 2.13.1.508.gb3defc5cc-goog In-Reply-To: <20170614215944.24984-1-jaghu@google.com> References: <20170614215944.24984-1-jaghu@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3987 Lines: 152 Inside the w1_slave_show function refactor the code to read the temp into a separate function. Signed-off-by: Jaghathiswari Rankappagounder Natarajan Change-Id: I35741f1345cd2bcb0754ca25c0258843af7ba579 --- drivers/w1/slaves/w1_therm.c | 82 +++++++++++++++++++++++++++----------------- 1 file changed, 51 insertions(+), 31 deletions(-) diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c index 82611f197b0a..88f4cc8c3908 100644 --- a/drivers/w1/slaves/w1_therm.c +++ b/drivers/w1/slaves/w1_therm.c @@ -64,6 +64,12 @@ struct w1_therm_family_data { atomic_t refcnt; }; +struct therm_info { + u8 rom[9]; + u8 crc; + u8 verdict; +}; + /* return the address of the refcnt in the family data */ #define THERM_REFCNT(family_data) \ (&((struct w1_therm_family_data *)family_data)->refcnt) @@ -427,33 +433,23 @@ static ssize_t w1_slave_store(struct device *device, return ret ? : size; } -static ssize_t w1_slave_show(struct device *device, - struct device_attribute *attr, char *buf) +static ssize_t read_therm(struct device *device, + struct w1_slave *sl, struct therm_info *info) { - struct w1_slave *sl = dev_to_w1_slave(device); struct w1_master *dev = sl->master; - u8 rom[9], crc, verdict, external_power; - int i, ret, max_trying = 10; - ssize_t c = PAGE_SIZE; - u8 *family_data = sl->family_data; + u8 external_power; + int ret, max_trying = 10; ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) goto post_unlock; - if (!sl->family_data) { - ret = -ENODEV; - goto pre_unlock; - } - - /* prevent the slave from going away in sleep */ - atomic_inc(THERM_REFCNT(family_data)); - memset(rom, 0, sizeof(rom)); + memset(info->rom, 0, sizeof(info->rom)); while (max_trying--) { - verdict = 0; - crc = 0; + info->verdict = 0; + info->crc = 0; if (!w1_reset_select_slave(sl)) { int count = 0; @@ -496,30 +492,57 @@ static ssize_t w1_slave_show(struct device *device, if (!w1_reset_select_slave(sl)) { w1_write_8(dev, W1_READ_SCRATCHPAD); - count = w1_read_block(dev, rom, 9); + count = w1_read_block(dev, info->rom, 9); if (count != 9) { dev_warn(device, "w1_read_block() " "returned %u instead of 9.\n", count); } - crc = w1_calc_crc8(rom, 8); + info->crc = w1_calc_crc8(info->rom, 8); - if (rom[8] == crc) - verdict = 1; + if (info->rom[8] == info->crc) + info->verdict = 1; } } - if (verdict) + if (info->verdict) break; } +pre_unlock: + mutex_unlock(&dev->bus_mutex); + +post_unlock: + return ret; +} + +static ssize_t w1_slave_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + u8 *family_data = sl->family_data; + struct therm_info info; + int ret; + ssize_t c = PAGE_SIZE; + int i; + + if (!sl->family_data) + return -ENODEV; + + /* prevent the slave from going away in sleep */ + atomic_inc(THERM_REFCNT(family_data)); + + ret = read_therm(device, sl, &info); + if (ret) + goto dec_refcnt; + for (i = 0; i < 9; ++i) - c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", rom[i]); + c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", info.rom[i]); c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n", - crc, (verdict) ? "YES" : "NO"); - if (verdict) - memcpy(family_data, rom, sizeof(rom)); + info.crc, (info.verdict) ? "YES" : "NO"); + if (info.verdict) + memcpy(family_data, info.rom, sizeof(info.rom)); else dev_warn(device, "Read failed CRC check\n"); @@ -528,13 +551,10 @@ static ssize_t w1_slave_show(struct device *device, ((u8 *)family_data)[i]); c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n", - w1_convert_temp(rom, sl->family->fid)); + w1_convert_temp(info.rom, sl->family->fid)); ret = PAGE_SIZE - c; -pre_unlock: - mutex_unlock(&dev->bus_mutex); - -post_unlock: +dec_refcnt: atomic_dec(THERM_REFCNT(family_data)); return ret; } -- 2.13.1.508.gb3defc5cc-goog