From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752840Ab2BUT2W (ORCPT ); Tue, 21 Feb 2012 14:28:22 -0500 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:49214 "EHLO opensource.wolfsonmicro.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752334Ab2BUT2V (ORCPT ); Tue, 21 Feb 2012 14:28:21 -0500 From: Mark Brown To: linux-kernel@vger.kernel.org Cc: patches@opensource.wolfsonmicro.com, Mark Brown Subject: [PATCH] regmap: Support raw reads from cached registers Date: Tue, 21 Feb 2012 19:28:18 +0000 Message-Id: <1329852498-28543-1-git-send-email-broonie@opensource.wolfsonmicro.com> X-Mailer: git-send-email 1.7.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fall back to a register by register read to do so; most likely we'll be cache only so the overhead will be low. Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 28 ++++++++++++++++++++++------ 1 files changed, 22 insertions(+), 6 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e015acd..e146b02 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -712,16 +712,32 @@ EXPORT_SYMBOL_GPL(regmap_read); int regmap_raw_read(struct regmap *map, unsigned int reg, void *val, size_t val_len) { - size_t val_count = val_len / map->format.val_bytes; - int ret; - - WARN_ON(!regmap_volatile_range(map, reg, val_count) && - map->cache_type != REGCACHE_NONE); + size_t val_bytes = map->format.val_bytes; + size_t val_count = val_len / val_bytes; + unsigned int v; + int ret, i; mutex_lock(&map->lock); - ret = _regmap_raw_read(map, reg, val, val_len); + if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass || + map->cache_type == REGCACHE_NONE) { + /* Physical block read if there's no cache involved */ + ret = _regmap_raw_read(map, reg, val, val_len); + + } else { + /* Otherwise go word by word for the cache; should be low + * cost as we expect to hit the cache. + */ + for (i = 0; i < val_count; i++) { + ret = _regmap_read(map, reg + i, &v); + if (ret != 0) + goto out; + + map->format.format_val(val + (i * val_bytes), v); + } + } + out: mutex_unlock(&map->lock); return ret; -- 1.7.9.1