[PATCH 1/3] dm: adc: add iMX93 ADC support
Bough Chen
haibo.chen at nxp.com
Fri Mar 17 03:54:31 CET 2023
> -----Original Message-----
> From: Luca Ellero <l.ellero at asem.it>
> Sent: 2023年3月15日 21:36
> To: u-boot at lists.denx.de; sbabic at denx.de; festevam at gmail.com; dl-uboot-imx
> <uboot-imx at nxp.com>; luca.ellero at brickedbrain.com; Ye Li <ye.li at nxp.com>;
> Peng Fan <peng.fan at nxp.com>; Bough Chen <haibo.chen at nxp.com>
> Cc: Luca Ellero <l.ellero at asem.it>
> Subject: [PATCH 1/3] dm: adc: add iMX93 ADC support
>
> This commit adds driver for iMX93 ADC.
>
> The driver is implemented using driver model and provides ADC uclass's methods
> for ADC single channel operations:
> - adc_start_channel()
> - adc_channel_data()
> - adc_stop()
>
> ADC features:
> - channels: 4
> - resolution: 12-bit
>
> Signed-off-by: Luca Ellero <l.ellero at asem.it>
> ---
> drivers/adc/Kconfig | 8 ++
> drivers/adc/Makefile | 1 +
> drivers/adc/imx93-adc.c | 286
> ++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 295 insertions(+)
> create mode 100644 drivers/adc/imx93-adc.c
>
> diff --git a/drivers/adc/Kconfig b/drivers/adc/Kconfig index
> e719c38bb3..4336732dee 100644
> --- a/drivers/adc/Kconfig
> +++ b/drivers/adc/Kconfig
> @@ -63,3 +63,11 @@ config STM32_ADC
> - core driver to deal with common resources
> - child driver to deal with individual ADC resources (declare ADC
> device and associated channels, start/stop conversions)
> +
> +config ADC_IMX93
> + bool "Enable NXP IMX93 ADC driver"
> + help
> + This enables basic driver for NXP IMX93 ADC.
> + It provides:
> + - 4 analog input channels
> + - 12-bit resolution
> diff --git a/drivers/adc/Makefile b/drivers/adc/Makefile index
> c1387f3a34..5336c82097 100644
> --- a/drivers/adc/Makefile
> +++ b/drivers/adc/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_ADC_SANDBOX) += sandbox.o
> obj-$(CONFIG_SARADC_ROCKCHIP) += rockchip-saradc.o
> obj-$(CONFIG_SARADC_MESON) += meson-saradc.o
> obj-$(CONFIG_STM32_ADC) += stm32-adc.o stm32-adc-core.o
> +obj-$(CONFIG_ADC_IMX93) += imx93-adc.o
> diff --git a/drivers/adc/imx93-adc.c b/drivers/adc/imx93-adc.c new file mode
> 100644 index 0000000000..b3bbea6c4e
> --- /dev/null
> +++ b/drivers/adc/imx93-adc.c
> @@ -0,0 +1,286 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2023 ASEM Srl
> + * Author: Luca Ellero <l.ellero at asem.it>
> + *
> + * Originally based on NXP linux-imx kernel v5.15
> +drivers/iio/adc/imx93_adc.c */
> +
> +#include <common.h>
> +#include <errno.h>
> +#include <dm.h>
> +#include <linux/bitfield.h>
> +#include <linux/iopoll.h>
> +#include <adc.h>
> +
> +#define IMX93_ADC_MCR 0x00
> +#define IMX93_ADC_MSR 0x04
> +#define IMX93_ADC_ISR 0x10
> +#define IMX93_ADC_IMR 0x20
> +#define IMX93_ADC_CIMR0 0x24
> +#define IMX93_ADC_CTR0 0x94
> +#define IMX93_ADC_NCMR0 0xA4
> +#define IMX93_ADC_PCDR0 0x100
> +#define IMX93_ADC_PCDR1 0x104
> +#define IMX93_ADC_PCDR2 0x108
> +#define IMX93_ADC_PCDR3 0x10c
> +#define IMX93_ADC_PCDR4 0x110
> +#define IMX93_ADC_PCDR5 0x114
> +#define IMX93_ADC_PCDR6 0x118
> +#define IMX93_ADC_PCDR7 0x11c
> +#define IMX93_ADC_CALSTAT 0x39C
> +
> +#define IMX93_ADC_MCR_MODE_MASK BIT(29)
> +#define IMX93_ADC_MCR_NSTART_MASK BIT(24)
> +#define IMX93_ADC_MCR_CALSTART_MASK BIT(14)
> +#define IMX93_ADC_MCR_ADCLKSE_MASK BIT(8)
> +#define IMX93_ADC_MCR_PWDN_MASK BIT(0)
> +
> +#define IMX93_ADC_MSR_CALFAIL_MASK BIT(30)
> +#define IMX93_ADC_MSR_CALBUSY_MASK BIT(29)
> +#define IMX93_ADC_MSR_ADCSTATUS_MASK GENMASK(2, 0)
> +
> +#define IMX93_ADC_ISR_EOC_MASK BIT(1)
> +
> +#define IMX93_ADC_IMR_EOC_MASK BIT(1)
> +#define IMX93_ADC_IMR_ECH_MASK BIT(0)
> +
> +#define IMX93_ADC_PCDR_CDATA_MASK GENMASK(11, 0)
> +
> +#define IDLE 0
> +#define POWER_DOWN 1
> +#define WAIT_STATE 2
> +#define BUSY_IN_CALIBRATION 3
> +#define SAMPLE 4
> +#define CONVERSION 6
> +
> +#define IMX93_ADC_MAX_CHANNEL 3
> +#define IMX93_ADC_DAT_MASK 0xfff
> +#define IMX93_ADC_TIMEOUT 100000
> +
> +struct imx93_adc_priv {
> + int active_channel;
> + void __iomem *regs;
> +};
> +
> +static int imx93_adc_power_down(struct imx93_adc_priv *adc) {
> + u32 mcr, msr;
> + int ret;
> +
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr |= FIELD_PREP(IMX93_ADC_MCR_PWDN_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + ret = readl_poll_timeout(adc->regs + IMX93_ADC_MSR, msr,
> + ((msr & IMX93_ADC_MSR_ADCSTATUS_MASK) == POWER_DOWN),
> 50);
> + if (ret == -ETIMEDOUT)
> + pr_warn("ADC not in power down mode, current MSR: %x\n", msr);
> +
> + return ret;
> +}
> +
> +static int imx93_adc_config_ad_clk(struct imx93_adc_priv *adc) {
> + u32 mcr;
> + int ret;
> +
> + /* put adc in power down mode */
> + ret = imx93_adc_power_down(adc);
> + if (ret < 0)
> + return ret;
> +
> + /* config the AD_CLK equal to bus clock */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr |= FIELD_PREP(IMX93_ADC_MCR_ADCLKSE_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + /* bring ADC out of power down state, in idle state */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr &= ~FIELD_PREP(IMX93_ADC_MCR_PWDN_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
Few same code in the following, better to use a function like imx93_adc_power_up() to do this.
You can refer to latest upstream linux imx93 ADC version, seems you just refer to the downstream driver.
https://elixir.bootlin.com/linux/v6.3-rc2/source/drivers/iio/adc/imx93_adc.c
> +
> + return ret;
> +}
> +
> +static int imx93_adc_calibration(struct imx93_adc_priv *adc) {
> + u32 mcr, msr, adc_status;
> + int ret;
> +
> + /* make sure ADC is in power down mode */
> + msr = readl(adc->regs + IMX93_ADC_MSR);
> +
> + adc_status = FIELD_GET(IMX93_ADC_MSR_ADCSTATUS_MASK, msr);
> + if (adc_status != POWER_DOWN) {
> + ret = imx93_adc_power_down(adc);
> + if (ret < 0)
> + return ret;
> + }
Directly power down the adc to simplify the code logic.
> +
> + /* config SAR controller operating clock */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr &= ~FIELD_PREP(IMX93_ADC_MCR_ADCLKSE_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + /* bring ADC out of power down state */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr &= ~FIELD_PREP(IMX93_ADC_MCR_PWDN_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
Use the function adc power up, to reduce the redundant code.
> +
> + /*
> + * we use the default TSAMP/NRSMPL/AVGEN in MCR,
> + * can add the setting of these bit if need
> + */
> +
> + /* run calibration */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr |= FIELD_PREP(IMX93_ADC_MCR_CALSTART_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + /* wait calibration to be finished */
> + ret = readl_poll_timeout(adc->regs + IMX93_ADC_MSR, msr,
> + !(msr & IMX93_ADC_MSR_CALBUSY_MASK), 2000000);
> + if (ret == -ETIMEDOUT) {
> + pr_warn("ADC calibration timeout\n");
> + return ret;
> + }
> +
> + /* check whether calbration is successful or not */
> + msr = readl(adc->regs + IMX93_ADC_MSR);
> + if (msr & IMX93_ADC_MSR_CALFAIL_MASK) {
> + pr_warn("ADC calibration failed!\n");
> + return -EAGAIN;
> + }
> +
> + return 0;
> +}
> +
> +static int imx93_adc_channel_data(struct udevice *dev, int channel,
> + unsigned int *data)
> +{
> + struct imx93_adc_priv *adc = dev_get_priv(dev);
> + u32 isr, pcda;
> + int ret;
> +
> + if (channel != adc->active_channel) {
> + pr_err("Requested channel is not active!\n");
> + return -EINVAL;
> + }
> +
> + ret = readl_poll_timeout(adc->regs + IMX93_ADC_ISR, isr,
> + (isr & IMX93_ADC_ISR_EOC_MASK), IMX93_ADC_TIMEOUT);
> +
> + /* clear interrupts */
> + writel(isr, adc->regs + IMX93_ADC_ISR);
> +
> + if (ret == -ETIMEDOUT) {
> + pr_warn("ADC conversion timeout!\n");
> + return ret;
> + }
> +
> + pcda = readl(adc->regs + IMX93_ADC_PCDR0 + channel * 4);
> +
> + *data = FIELD_GET(IMX93_ADC_PCDR_CDATA_MASK, pcda);
> +
> + return 0;
> +}
> +
> +static int imx93_adc_start_channel(struct udevice *dev, int channel) {
> + struct imx93_adc_priv *adc = dev_get_priv(dev);
> + u32 imr, mcr;
> +
> + /* config channel mask register */
> + writel(1 << channel, adc->regs + IMX93_ADC_NCMR0);
> +
> + /* config interrupt mask */
> + imr = FIELD_PREP(IMX93_ADC_IMR_EOC_MASK, 1);
> + writel(imr, adc->regs + IMX93_ADC_IMR);
> + writel(1 << channel, adc->regs + IMX93_ADC_CIMR0);
> +
> + /* config one-shot mode */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr &= ~FIELD_PREP(IMX93_ADC_MCR_MODE_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + /* start normal conversion */
> + mcr = readl(adc->regs + IMX93_ADC_MCR);
> + mcr |= FIELD_PREP(IMX93_ADC_MCR_NSTART_MASK, 1);
> + writel(mcr, adc->regs + IMX93_ADC_MCR);
> +
> + adc->active_channel = channel;
> +
> + return 0;
> +}
> +
> +static int imx93_adc_stop(struct udevice *dev) {
> + struct imx93_adc_priv *adc = dev_get_priv(dev);
> +
> + imx93_adc_power_down(adc);
> +
> + adc->active_channel = -1;
> +
> + return 0;
> +}
> +
> +static int imx93_adc_probe(struct udevice *dev) {
> + struct imx93_adc_priv *adc = dev_get_priv(dev);
> + unsigned int ret;
> +
> + ret = imx93_adc_calibration(adc);
> + if (ret < 0)
> + return ret;
> +
> + ret = imx93_adc_config_ad_clk(adc);
> + if (ret < 0)
> + return ret;
> +
> + adc->active_channel = -1;
> +
> + return 0;
> +}
> +
> +static int imx93_adc_of_to_plat(struct udevice *dev) {
> + struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev);
> + struct imx93_adc_priv *adc = dev_get_priv(dev);
> +
> + adc->regs = dev_read_addr_ptr(dev);
> + if (adc->regs == (struct imx93_adc *)FDT_ADDR_T_NONE) {
> + pr_err("Dev: %s - can't get address!", dev->name);
> + return -ENODATA;
> + }
> +
> + uc_pdata->data_mask = IMX93_ADC_DAT_MASK;
> + uc_pdata->data_format = ADC_DATA_FORMAT_BIN;
> + uc_pdata->data_timeout_us = IMX93_ADC_TIMEOUT;
> +
> + /* Mask available channel bits: [0:3] */
> + uc_pdata->channel_mask = (2 << IMX93_ADC_MAX_CHANNEL) - 1;
Seems you forget to handle the ADC ipg clock: IMX93_CLK_ADC1_GATE, please add it in the driver.
Best Regards
Haibo Chen
> +
> + return 0;
> +}
> +
> +static const struct adc_ops imx93_adc_ops = {
> + .start_channel = imx93_adc_start_channel,
> + .channel_data = imx93_adc_channel_data,
> + .stop = imx93_adc_stop,
> +};
> +
> +static const struct udevice_id imx93_adc_ids[] = {
> + { .compatible = "nxp,imx93-adc" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(imx93_adc) = {
> + .name = "imx93-adc",
> + .id = UCLASS_ADC,
> + .of_match = imx93_adc_ids,
> + .ops = &imx93_adc_ops,
> + .probe = imx93_adc_probe,
> + .of_to_plat = imx93_adc_of_to_plat,
> + .priv_auto = sizeof(struct imx93_adc_priv),
> +};
> --
> 2.25.1
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