Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755205AbYKFNoW (ORCPT ); Thu, 6 Nov 2008 08:44:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754568AbYKFNnR (ORCPT ); Thu, 6 Nov 2008 08:43:17 -0500 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:60247 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754114AbYKFNnJ (ORCPT ); Thu, 6 Nov 2008 08:43:09 -0500 From: Mark Brown To: Samuel Ortiz Cc: linux-kernel@vger.kernel.org, Mark Brown Subject: [PATCH 4/4] mfd: Add AUXADC support for WM8350 Date: Thu, 6 Nov 2008 13:43:06 +0000 Message-Id: <1225978986-25990-4-git-send-email-broonie@opensource.wolfsonmicro.com> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <1225978986-25990-3-git-send-email-broonie@opensource.wolfsonmicro.com> References: <20081106134254.GA21855@rakim.wolfsonmicro.main> <1225978986-25990-1-git-send-email-broonie@opensource.wolfsonmicro.com> <1225978986-25990-2-git-send-email-broonie@opensource.wolfsonmicro.com> <1225978986-25990-3-git-send-email-broonie@opensource.wolfsonmicro.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3707 Lines: 124 The auxiliary ADC in the WM8350 is shared between several subdevices so access to it needs to be arbitrated by the core driver. Signed-off-by: Mark Brown --- drivers/mfd/wm8350-core.c | 51 ++++++++++++++++++++++++++++++++- include/linux/mfd/wm8350/comparator.h | 8 +++++ include/linux/mfd/wm8350/core.h | 2 + 3 files changed, 60 insertions(+), 1 deletions(-) diff --git a/drivers/mfd/wm8350-core.c b/drivers/mfd/wm8350-core.c index c013afd..60439bd 100644 --- a/drivers/mfd/wm8350-core.c +++ b/drivers/mfd/wm8350-core.c @@ -63,7 +63,6 @@ */ static DEFINE_MUTEX(io_mutex); static DEFINE_MUTEX(reg_lock_mutex); -static DEFINE_MUTEX(auxadc_mutex); /* Perform a physical read from the device. */ @@ -1082,6 +1081,55 @@ int wm8350_unmask_irq(struct wm8350 *wm8350, int irq) } EXPORT_SYMBOL_GPL(wm8350_unmask_irq); +int wm8350_read_auxadc(struct wm8350 *wm8350, int channel, int scale, int vref) +{ + u16 reg, result = 0; + int tries = 5; + + if (channel < WM8350_AUXADC_AUX1 || channel > WM8350_AUXADC_TEMP) + return -EINVAL; + if (channel >= WM8350_AUXADC_USB && channel <= WM8350_AUXADC_TEMP + && (scale != 0 || vref != 0)) + return -EINVAL; + + mutex_lock(&wm8350->auxadc_mutex); + + /* Turn on the ADC */ + reg = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5); + wm8350_reg_write(wm8350, WM8350_POWER_MGMT_5, reg | WM8350_AUXADC_ENA); + + if (scale || vref) { + reg = scale << 13; + reg |= vref << 12; + wm8350_reg_write(wm8350, WM8350_AUX1_READBACK + channel, reg); + } + + reg = wm8350_reg_read(wm8350, WM8350_DIGITISER_CONTROL_1); + reg |= 1 << channel | WM8350_AUXADC_POLL; + wm8350_reg_write(wm8350, WM8350_DIGITISER_CONTROL_1, reg); + + do { + schedule_timeout_interruptible(1); + reg = wm8350_reg_read(wm8350, WM8350_DIGITISER_CONTROL_1); + } while (tries-- && (reg & WM8350_AUXADC_POLL)); + + if (!tries) + dev_err(wm8350->dev, "adc chn %d read timeout\n", channel); + else + result = wm8350_reg_read(wm8350, + WM8350_AUX1_READBACK + channel); + + /* Turn off the ADC */ + reg = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5); + wm8350_reg_write(wm8350, WM8350_POWER_MGMT_5, + reg & ~WM8350_AUXADC_ENA); + + mutex_unlock(&wm8350->auxadc_mutex); + + return result & WM8350_AUXADC_DATA1_MASK; +} +EXPORT_SYMBOL_GPL(wm8350_read_auxadc); + /* * Cache is always host endian. */ @@ -1239,6 +1287,7 @@ int wm8350_device_init(struct wm8350 *wm8350, int irq, } } + mutex_init(&wm8350->auxadc_mutex); mutex_init(&wm8350->irq_mutex); INIT_WORK(&wm8350->irq_work, wm8350_irq_worker); if (irq) { diff --git a/include/linux/mfd/wm8350/comparator.h b/include/linux/mfd/wm8350/comparator.h index 0537886..54bc5d0 100644 --- a/include/linux/mfd/wm8350/comparator.h +++ b/include/linux/mfd/wm8350/comparator.h @@ -164,4 +164,12 @@ #define WM8350_AUXADC_BATT 6 #define WM8350_AUXADC_TEMP 7 +struct wm8350; + +/* + * AUX ADC Readback + */ +int wm8350_read_auxadc(struct wm8350 *wm8350, int channel, int scale, + int vref); + #endif diff --git a/include/linux/mfd/wm8350/core.h b/include/linux/mfd/wm8350/core.h index 9490ec1..cc19005 100644 --- a/include/linux/mfd/wm8350/core.h +++ b/include/linux/mfd/wm8350/core.h @@ -573,6 +573,8 @@ struct wm8350 { void *src); u16 *reg_cache; + struct mutex auxadc_mutex; + /* Interrupt handling */ struct work_struct irq_work; struct mutex irq_mutex; /* IRQ table mutex */ -- 1.5.6.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/