Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756514Ab2BBPE1 (ORCPT ); Thu, 2 Feb 2012 10:04:27 -0500 Received: from mail.work-microwave.de ([62.245.205.51]:35598 "EHLO work-microwave.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751766Ab2BBPEY (ORCPT ); Thu, 2 Feb 2012 10:04:24 -0500 From: stigge@antcom.de To: w.sang@pengutronix.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, kevin.wells@nxp.com, linux-arm-kernel@lists.infradead.org, jic23@cam.ac.uk, gregkh@linuxfoundation.org, linux-iio@vger.kernel.org, devel@driverdev.osuosl.org Cc: Roland Stigge Subject: [PATCH] ARM: LPC32xx: ADC support Date: Thu, 2 Feb 2012 16:02:58 +0100 Message-Id: <1328194978-20064-1-git-send-email-stigge@antcom.de> X-Mailer: git-send-email 1.7.8.3 X-FEAS-SYSTEM-WL: rst@work-microwave.de, 192.168.11.78 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12468 Lines: 435 This patch adds a 3-channel ADC driver for the LPC32xx ARM SoC Signed-off-by: Roland Stigge diff --git a/arch/arm/mach-lpc32xx/clock.c b/arch/arm/mach-lpc32xx/clock.c index c269ef5..9cda6fa 100644 --- a/arch/arm/mach-lpc32xx/clock.c +++ b/arch/arm/mach-lpc32xx/clock.c @@ -760,6 +760,36 @@ static struct clk clk_tsc = { .get_rate = local_return_parent_rate, }; +static int adc_onoff_enable(struct clk *clk, int enable) +{ + u32 tmp; + + /* Use PERIPH_CLOCK */ + tmp = __raw_readl(LPC32XX_CLKPWR_ADC_CLK_CTRL_1); + tmp |= LPC32XX_CLKPWR_ADCCTRL1_PCLK_SEL; + /* + * Set clock divider so that we have equal to or less than + * 4.5MHz clock at ADC + */ + tmp |= clk->get_rate(clk) / 4500000 + 1; + __raw_writel(tmp, LPC32XX_CLKPWR_ADC_CLK_CTRL_1); + + if (enable == 0) + __raw_writel(0, clk->enable_reg); + else + __raw_writel(clk->enable_mask, clk->enable_reg); + + return 0; +} + +static struct clk clk_adc = { + .parent = &clk_pclk, + .enable = adc_onoff_enable, + .enable_reg = LPC32XX_CLKPWR_ADC_CLK_CTRL, + .enable_mask = LPC32XX_CLKPWR_ADC32CLKCTRL_CLK_EN, + .get_rate = local_return_parent_rate, +}; + static int mmc_onoff_enable(struct clk *clk, int enable) { u32 tmp; @@ -1097,6 +1127,7 @@ static struct clk_lookup lookups[] = { _REGISTER_CLOCK("dev:ssp1", NULL, clk_ssp1) _REGISTER_CLOCK("lpc32xx_keys.0", NULL, clk_kscan) _REGISTER_CLOCK("lpc32xx-nand.0", "nand_ck", clk_nand) + _REGISTER_CLOCK("lpc32xx-adc", NULL, clk_adc) _REGISTER_CLOCK(NULL, "i2s0_ck", clk_i2s0) _REGISTER_CLOCK(NULL, "i2s1_ck", clk_i2s1) _REGISTER_CLOCK("ts-lpc32xx", NULL, clk_tsc) diff --git a/arch/arm/mach-lpc32xx/common.c b/arch/arm/mach-lpc32xx/common.c index f220eb0..2f869c0 100644 --- a/arch/arm/mach-lpc32xx/common.c +++ b/arch/arm/mach-lpc32xx/common.c @@ -137,6 +137,27 @@ struct platform_device lpc32xx_rtc_device = { .resource = lpc32xx_rtc_resources, }; +/* + * ADC support + */ +static struct resource adc_resources[] = { + { + .start = LPC32XX_ADC_BASE, + .end = LPC32XX_ADC_BASE + SZ_4K - 1, + .flags = IORESOURCE_MEM, + }, { + .start = IRQ_LPC32XX_TS_IRQ, + .end = IRQ_LPC32XX_TS_IRQ, + .flags = IORESOURCE_IRQ, + }, +}; +struct platform_device lpc32xx_adc_device = { + .name = "lpc32xx-adc", + .id = -1, + .num_resources = ARRAY_SIZE(adc_resources), + .resource = adc_resources, +}; + #if defined(CONFIG_USB_OHCI_HCD) /* The dmamask must be set for OHCI to work */ static u64 ohci_dmamask = ~(u32) 0; diff --git a/arch/arm/mach-lpc32xx/common.h b/arch/arm/mach-lpc32xx/common.h index e42d702..5bf0050 100644 --- a/arch/arm/mach-lpc32xx/common.h +++ b/arch/arm/mach-lpc32xx/common.h @@ -30,6 +30,7 @@ extern struct platform_device lpc32xx_i2c0_device; extern struct platform_device lpc32xx_i2c1_device; extern struct platform_device lpc32xx_i2c2_device; extern struct platform_device lpc32xx_tsc_device; +extern struct platform_device lpc32xx_adc_device; extern struct platform_device lpc32xx_rtc_device; extern struct platform_device lpc32xx_ohci_device; diff --git a/arch/arm/mach-lpc32xx/phy3250.c b/arch/arm/mach-lpc32xx/phy3250.c index 69a5ceb..23b484c 100644 --- a/arch/arm/mach-lpc32xx/phy3250.c +++ b/arch/arm/mach-lpc32xx/phy3250.c @@ -317,6 +317,9 @@ static struct platform_device *phy3250_devs[] __initdata = { #if defined(CONFIG_LPC_ENET) &lpc32xx_net_device, #endif +#if defined(CONFIG_LPC32XX_ADC) + &lpc32xx_adc_device, +#endif }; static struct amba_device *amba_devs[] __initdata = { diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig index d9decea..592eabd 100644 --- a/drivers/staging/iio/adc/Kconfig +++ b/drivers/staging/iio/adc/Kconfig @@ -193,4 +193,13 @@ config MAX1363_RING_BUFFER Say yes here to include ring buffer support in the MAX1363 ADC driver. +config LPC32XX_ADC + tristate "NXP LPC32XX ADC" + depends on ARCH_LPC32XX && !TOUCHSCREEN_LPC32XX + help + Say yes here to build support for the integrated ADC inside the + LPC32XX SoC. Note that this feature uses the same hardware as the + touchscreen driver, so you can only select one of the two drivers + (lpc32xx_adc or lpc32xx_ts). Provides direct access via sysfs. + endmenu diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile index ceee7f3..f83ab95 100644 --- a/drivers/staging/iio/adc/Makefile +++ b/drivers/staging/iio/adc/Makefile @@ -37,3 +37,4 @@ obj-$(CONFIG_AD7192) += ad7192.o obj-$(CONFIG_ADT7310) += adt7310.o obj-$(CONFIG_ADT7410) += adt7410.o obj-$(CONFIG_AD7280) += ad7280a.o +obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o diff --git a/drivers/staging/iio/adc/lpc32xx_adc.c b/drivers/staging/iio/adc/lpc32xx_adc.c new file mode 100644 index 0000000..6b27446 --- /dev/null +++ b/drivers/staging/iio/adc/lpc32xx_adc.c @@ -0,0 +1,286 @@ +/* + * lpc32xx_adc.c - Support for ADC in LPC32XX + * + * Copyright (C) 2011 Roland Stigge + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../iio.h" +#include "../sysfs.h" + +/* + * LPC32XX registers definitions + */ + +#define LPC32XX_ADC_SELECT(x) ((x) + 0x04) +#define LPC32XX_ADC_CTRL(x) ((x) + 0x08) +#define LPC32XX_ADC_VALUE(x) ((x) + 0x48) + +/* Bit definitions for LPC32XX_ADC_SELECT: */ +#define AD_REFm 0x00000200 /* constant, always write this value! */ +#define AD_REFp 0x00000080 /* constant, always write this value! */ +#define AD_IN 0x00000010 /* multiple of this is the */ + /* channel number: 0, 1, 2 */ +#define AD_INTERNAL 0x00000004 /* constant, always write this value! */ + +/* Bit definitions for LPC32XX_ADC_CTRL: */ +#define AD_STROBE 0x00000002 +#define AD_PDN_CTRL 0x00000004 + +/* Bit definitions for LPC32XX_ADC_VALUE: */ +#define ADC_VALUE_MASK 0x000003FF + +#define MOD_NAME "lpc32xx-adc" + +/* + * chip specifc information + */ + +struct lpc32xx_adc_info { + struct iio_dev *dev; + void __iomem *adc_base; + int irq; + struct clk *clk; + struct completion completion; + + u32 value; +}; + +/* + * sysfs nodes + */ +static ssize_t lpc32xx_adin_value(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct lpc32xx_adc_info *info = iio_priv(dev_info); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int result; + + mutex_lock(&dev_info->mlock); + /* Measurement setup */ + __raw_writel(AD_INTERNAL | (AD_IN * this_attr->address) | + AD_REFp | AD_REFm, + LPC32XX_ADC_SELECT(info->adc_base)); + /* Trigger conversion */ + __raw_writel(AD_PDN_CTRL | AD_STROBE, + LPC32XX_ADC_CTRL(info->adc_base)); + + wait_for_completion(&info->completion); /* set by ISR */ + + result = sprintf(buf, "%d\n", info->value); + + mutex_unlock(&dev_info->mlock); + + return result; +} + +static IIO_DEVICE_ATTR(in0_raw, S_IRUGO, lpc32xx_adin_value, NULL, 0); +static IIO_DEVICE_ATTR(in1_raw, S_IRUGO, lpc32xx_adin_value, NULL, 1); +static IIO_DEVICE_ATTR(in2_raw, S_IRUGO, lpc32xx_adin_value, NULL, 2); + +static struct attribute *lpc32xx_adin_attributes[] = { + &iio_dev_attr_in0_raw.dev_attr.attr, + &iio_dev_attr_in1_raw.dev_attr.attr, + &iio_dev_attr_in2_raw.dev_attr.attr, + NULL, +}; + +static const struct attribute_group lpc32xx_adin_attribute_group = { + .attrs = lpc32xx_adin_attributes, +}; + +static const struct iio_info lpc32xx_adc_iio_info = { + .attrs = &lpc32xx_adin_attribute_group, + .driver_module = THIS_MODULE, +}; + +static irqreturn_t lpc32xx_adc_isr(int irq, void *dev_id) +{ + struct lpc32xx_adc_info *info = (struct lpc32xx_adc_info *) dev_id; + + /* Read value and clear irq */ + info->value = __raw_readl(LPC32XX_ADC_VALUE(info->adc_base)) & + ADC_VALUE_MASK; + complete(&info->completion); + + return IRQ_HANDLED; +} + +static int __devinit lpc32xx_adc_probe(struct platform_device *pdev) +{ + struct lpc32xx_adc_info *info = NULL; + struct resource *res; + int retval = -ENODEV; + struct iio_dev *iodev = NULL; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "failed to get platform I/O memory\n"); + retval = -EBUSY; + goto errout1; + } + + iodev = iio_allocate_device(sizeof(struct lpc32xx_adc_info)); + if (!iodev) { + dev_err(&pdev->dev, "failed allocating iio device\n"); + retval = -ENOMEM; + goto errout1; + } + + info = iio_priv(iodev); + info->dev = iodev; + + info->adc_base = ioremap(res->start, res->end - res->start + 1); + if (!info->adc_base) { + dev_err(&pdev->dev, "failed mapping memory\n"); + retval = -EBUSY; + goto errout3; + } + + iodev->name = MOD_NAME; + iodev->dev.parent = &pdev->dev; + iodev->info = &lpc32xx_adc_iio_info; + iodev->modes = INDIO_DIRECT_MODE; + + retval = iio_device_register(iodev); + if (retval) + goto errout4; + + info->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(info->clk)) { + dev_err(&pdev->dev, "failed getting clock\n"); + goto errout5; + } + clk_enable(info->clk); + + info->irq = platform_get_irq(pdev, 0); + if ((info->irq < 0) || (info->irq >= NR_IRQS)) { + dev_err(&pdev->dev, "failed getting interrupt resource\n"); + retval = -EINVAL; + goto errout6; + } + + retval = request_irq(info->irq, lpc32xx_adc_isr, 0, MOD_NAME, info); + if (retval < 0) { + dev_err(&pdev->dev, "failed requesting interrupt\n"); + goto errout6; + } + + platform_set_drvdata(pdev, info); + + device_init_wakeup(&pdev->dev, 1); + init_completion(&info->completion); + + printk(KERN_INFO "LPC32XX ADC driver loaded, IRQ %d\n", info->irq); + + return 0; + +errout6: + clk_disable(info->clk); + clk_put(info->clk); +errout5: + iio_device_unregister(info->dev); +errout4: + iounmap(info->adc_base); +errout3: + iio_free_device(info->dev); +errout1: + return retval; +} + +static int __devexit lpc32xx_adc_remove(struct platform_device *pdev) +{ + struct lpc32xx_adc_info *info = platform_get_drvdata(pdev); + + free_irq(info->irq, info->dev); + platform_set_drvdata(pdev, NULL); + clk_disable(info->clk); + clk_put(info->clk); + iio_device_unregister(info->dev); + iio_free_device(info->dev); + iounmap(info->adc_base); + kfree(info); + + printk(KERN_INFO "LPC32XX ADC driver unloaded\n"); + + return 0; +} + +#if defined(CONFIG_SUSPEND) +static int lpc32xx_adc_suspend(struct device *dev) +{ + struct lpc32xx_adc_info *info = dev_get_drvdata(dev); + + clk_disable(info->clk); + return 0; +} + +static int lpc32xx_adc_resume(struct device *dev) +{ + struct lpc32xx_adc_info *info = dev_get_drvdata(dev); + + clk_enable(info->clk); + return 0; +} + +static const struct dev_pm_ops lpc32xx_adc_pm_ops = { + .suspend = lpc32xx_adc_suspend, + .resume = lpc32xx_adc_resume, +}; +#define LPC32XX_ADC_PM_OPS (&lpc32xx_adc_pm_ops) +#else +#define LPC32XX_ADC_PM_OPS NULL +#endif + +static struct platform_driver lpc32xx_adc_driver = { + .probe = lpc32xx_adc_probe, + .remove = __devexit_p(lpc32xx_adc_remove), + .driver = { + .name = MOD_NAME, + .owner = THIS_MODULE, + .pm = LPC32XX_ADC_PM_OPS, + }, +}; + +static int __init lpc32xx_adc_init(void) +{ + return platform_driver_register(&lpc32xx_adc_driver); +} + +static void __exit lpc32xx_adc_exit(void) +{ + platform_driver_unregister(&lpc32xx_adc_driver); +} + +module_init(lpc32xx_adc_init); +module_exit(lpc32xx_adc_exit); + +MODULE_AUTHOR("Roland Stigge "); +MODULE_DESCRIPTION("LPC32XX ADC driver"); +MODULE_LICENSE("GPL"); -- 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/