Re: [PATCH v2 04/10] iio: adc: at91-sama5d2_adc: convert to platform specific data structures

Jonathan Cameron
2021-08-30T12:20:31Z

On Tue, 24 Aug 2021 14:54:35 +0300
Eugen Hristev <eugen.hristev@microchip.com> wrote:

> Convert the driver to platform specific structures. This means:
> - create a register layout struct that will hold offsets for registers
> - create a platform struct that will hold platform information (number of
> channels, indexes for different channels and pointer to layout struct)
> - convert specific macros that are platform dependent into platform variables
>
> This step is in fact a no-op, but allows the driver to be more flexible
> and for future enhancement including adding new platforms that are partly
> compatible with the current driver and differ slightly in register layout
> or capabilities for example.
>
> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 410 +++++++++++++++++------------
> 1 file changed, 247 insertions(+), 163 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index 9d71dcffcf93..8ede18b8d789 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -27,8 +27,9 @@
> #include <linux/pinctrl/consumer.h>
> #include <linux/regulator/consumer.h>
>
> +struct at91_adc_reg_layout {
> /* Control Register */
> -#define AT91_SAMA5D2_CR 0x00
> + u16 CR;
> /* Software Reset */
> #define AT91_SAMA5D2_CR_SWRST BIT(0)
> /* Start Conversion */
> @@ -39,7 +40,7 @@
> #define AT91_SAMA5D2_CR_CMPRST BIT(4)
>
> /* Mode Register */
> -#define AT91_SAMA5D2_MR 0x04
> + u16 MR;
> /* Trigger Selection */
> #define AT91_SAMA5D2_MR_TRGSEL(v) ((v) << 1)
> /* ADTRG */
> @@ -82,19 +83,19 @@
> #define AT91_SAMA5D2_MR_USEQ BIT(31)
>
> /* Channel Sequence Register 1 */
> -#define AT91_SAMA5D2_SEQR1 0x08
> + u16 SEQR1;
> /* Channel Sequence Register 2 */
> -#define AT91_SAMA5D2_SEQR2 0x0c
> + u16 SEQR2;
> /* Channel Enable Register */
> -#define AT91_SAMA5D2_CHER 0x10
> + u16 CHER;
> /* Channel Disable Register */
> -#define AT91_SAMA5D2_CHDR 0x14
> + u16 CHDR;
> /* Channel Status Register */
> -#define AT91_SAMA5D2_CHSR 0x18
> + u16 CHSR;
> /* Last Converted Data Register */
> -#define AT91_SAMA5D2_LCDR 0x20
> + u16 LCDR;
> /* Interrupt Enable Register */
> -#define AT91_SAMA5D2_IER 0x24
> + u16 IER;
> /* Interrupt Enable Register - TS X measurement ready */
> #define AT91_SAMA5D2_IER_XRDY BIT(20)
> /* Interrupt Enable Register - TS Y measurement ready */
> @@ -109,22 +110,23 @@
> #define AT91_SAMA5D2_IER_PEN BIT(29)
> /* Interrupt Enable Register - No pen detect */
> #define AT91_SAMA5D2_IER_NOPEN BIT(30)
> +
> /* Interrupt Disable Register */
> -#define AT91_SAMA5D2_IDR 0x28
> + u16 IDR;
> /* Interrupt Mask Register */
> -#define AT91_SAMA5D2_IMR 0x2c
> + u16 IMR;
> /* Interrupt Status Register */
> -#define AT91_SAMA5D2_ISR 0x30
> + u16 ISR;
> /* Interrupt Status Register - Pen touching sense status */
> #define AT91_SAMA5D2_ISR_PENS BIT(31)
> /* Last Channel Trigger Mode Register */
> -#define AT91_SAMA5D2_LCTMR 0x34
> + u16 LCTMR;
> /* Last Channel Compare Window Register */
> -#define AT91_SAMA5D2_LCCWR 0x38
> + u16 LCCWR;
> /* Overrun Status Register */
> -#define AT91_SAMA5D2_OVER 0x3c
> + u16 OVER;
> /* Extended Mode Register */
> -#define AT91_SAMA5D2_EMR 0x40
> + u16 EMR;
> /* Extended Mode Register - Oversampling rate */
> #define AT91_SAMA5D2_EMR_OSR(V) ((V) << 16)
> #define AT91_SAMA5D2_EMR_OSR_MASK GENMASK(17, 16)
> @@ -134,22 +136,22 @@
>
> /* Extended Mode Register - Averaging on single trigger event */
> #define AT91_SAMA5D2_EMR_ASTE(V) ((V) << 20)
> +
> /* Compare Window Register */
> -#define AT91_SAMA5D2_CWR 0x44
> + u16 CWR;
> /* Channel Gain Register */
> -#define AT91_SAMA5D2_CGR 0x48
> -
> + u16 CGR;
> /* Channel Offset Register */
> -#define AT91_SAMA5D2_COR 0x4c
> + u16 COR;
> #define AT91_SAMA5D2_COR_DIFF_OFFSET 16
>
> /* Analog Control Register */
> -#define AT91_SAMA5D2_ACR 0x94
> + u16 ACR;
> /* Analog Control Register - Pen detect sensitivity mask */
> #define AT91_SAMA5D2_ACR_PENDETSENS_MASK GENMASK(1, 0)
>
> /* Touchscreen Mode Register */
> -#define AT91_SAMA5D2_TSMR 0xb0
> + u16 TSMR;
> /* Touchscreen Mode Register - No touch mode */
> #define AT91_SAMA5D2_TSMR_TSMODE_NONE 0
> /* Touchscreen Mode Register - 4 wire screen, no pressure measurement */
> @@ -178,13 +180,13 @@
> #define AT91_SAMA5D2_TSMR_PENDET_ENA BIT(24)
>
> /* Touchscreen X Position Register */
> -#define AT91_SAMA5D2_XPOSR 0xb4
> + u16 XPOSR;
> /* Touchscreen Y Position Register */
> -#define AT91_SAMA5D2_YPOSR 0xb8
> + u16 YPOSR;
> /* Touchscreen Pressure Register */
> -#define AT91_SAMA5D2_PRESSR 0xbc
> + u16 PRESSR;
> /* Trigger Register */
> -#define AT91_SAMA5D2_TRGR 0xc0
> + u16 TRGR;
> /* Mask for TRGMOD field of TRGR register */
> #define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0)
> /* No trigger, only software trigger can start conversions */
> @@ -203,30 +205,52 @@
> #define AT91_SAMA5D2_TRGR_TRGPER(x) ((x) << 16)
>
> /* Correction Select Register */
> -#define AT91_SAMA5D2_COSR 0xd0
> + u16 COSR;
> /* Correction Value Register */
> -#define AT91_SAMA5D2_CVR 0xd4
> + u16 CVR;
> /* Channel Error Correction Register */
> -#define AT91_SAMA5D2_CECR 0xd8
> + u16 CECR;
> /* Write Protection Mode Register */
> -#define AT91_SAMA5D2_WPMR 0xe4
> + u16 WPMR;
> /* Write Protection Status Register */
> -#define AT91_SAMA5D2_WPSR 0xe8
> + u16 WPSR;
> /* Version Register */
> -#define AT91_SAMA5D2_VERSION 0xfc
> -
> -#define AT91_SAMA5D2_HW_TRIG_CNT 3
> -#define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
> -#define AT91_SAMA5D2_DIFF_CHAN_CNT 6
> -
> -#define AT91_SAMA5D2_TIMESTAMP_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \
> - AT91_SAMA5D2_DIFF_CHAN_CNT + 1)
> + u16 VERSION;
> +};
>
> -#define AT91_SAMA5D2_TOUCH_X_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \
> - AT91_SAMA5D2_DIFF_CHAN_CNT * 2)
> -#define AT91_SAMA5D2_TOUCH_Y_CHAN_IDX (AT91_SAMA5D2_TOUCH_X_CHAN_IDX + 1)
> -#define AT91_SAMA5D2_TOUCH_P_CHAN_IDX (AT91_SAMA5D2_TOUCH_Y_CHAN_IDX + 1)
> -#define AT91_SAMA5D2_MAX_CHAN_IDX AT91_SAMA5D2_TOUCH_P_CHAN_IDX
> +static const struct at91_adc_reg_layout sama5d2_layout = {
> + .CR = 0x00,
> + .MR = 0x04,
> + .SEQR1 = 0x08,
> + .SEQR2 = 0x0c,
> + .CHER = 0x10,
> + .CHDR = 0x14,
> + .CHSR = 0x18,
> + .LCDR = 0x20,
> + .IER = 0x24,
> + .IDR = 0x28,
> + .IMR = 0x2c,
> + .ISR = 0x30,
> + .LCTMR = 0x34,
> + .LCCWR = 0x38,
> + .OVER = 0x3c,
> + .EMR = 0x40,
> + .CWR = 0x44,
> + .CGR = 0x48,
> + .COR = 0x4c,
> + .ACR = 0x94,
> + .TSMR = 0xb0,
> + .XPOSR = 0xb4,
> + .YPOSR = 0xb8,
> + .PRESSR = 0xbc,
> + .TRGR = 0xc0,
> + .COSR = 0xd0,
> + .CVR = 0xd4,
> + .CECR = 0xd8,
> + .WPMR = 0xe4,
> + .WPSR = 0xe8,
> + .VERSION = 0xfc,
> +};
>
> #define AT91_SAMA5D2_TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */
> #define AT91_SAMA5D2_TOUCH_PEN_DETECT_DEBOUNCE_US 200
> @@ -235,18 +259,6 @@
>
> #define AT91_SAMA5D2_MAX_POS_BITS 12
>
> -/*
> - * Maximum number of bytes to hold conversion from all channels
> - * without the timestamp.
> - */
> -#define AT91_BUFFER_MAX_CONVERSION_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \
> - AT91_SAMA5D2_DIFF_CHAN_CNT) * 2)
> -
> -/* This total must also include the timestamp */
> -#define AT91_BUFFER_MAX_BYTES (AT91_BUFFER_MAX_CONVERSION_BYTES + 8)
> -
> -#define AT91_BUFFER_MAX_HWORDS (AT91_BUFFER_MAX_BYTES / 2)
> -
> #define AT91_HWFIFO_MAX_SIZE_STR "128"
> #define AT91_HWFIFO_MAX_SIZE 128
>
> @@ -255,12 +267,12 @@
> #define AT91_OSR_4SAMPLES 4
> #define AT91_OSR_16SAMPLES 16
>
> -#define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
> +#define AT91_SAMA5D2_CHAN_SINGLE(index, num, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> .address = addr, \
> - .scan_index = num, \
> + .scan_index = index, \
> .scan_type = { \
> .sign = 'u', \
> .realbits = 14, \
> @@ -274,14 +286,14 @@
> .indexed = 1, \
> }
>
> -#define AT91_SAMA5D2_CHAN_DIFF(num, num2, addr) \
> +#define AT91_SAMA5D2_CHAN_DIFF(index, num, num2, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .differential = 1, \
> .channel = num, \
> .channel2 = num2, \
> .address = addr, \
> - .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \
> + .scan_index = index, \
> .scan_type = { \
> .sign = 's', \
> .realbits = 14, \
> @@ -328,13 +340,48 @@
> .datasheet_name = name, \
> }
>
> -#define at91_adc_readl(st, reg) readl_relaxed(st->base + reg)
> -#define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg)
> +#define at91_adc_readl(st, reg) \
> + readl_relaxed((st)->base + (st)->soc_info.platform->layout->reg)
I was a bit in two minds about whether this should be in capitals to make it clear
macro magic is going on, or whether lowercase is fine. In the end I couldn't make
up my mind so will accept it like this! :)

Jonathan