Re: [PATCH v5 06/10] iio: dac: adi-axi-dac: extend features
From: Angelo Dureghello
Date: Fri Oct 11 2024 - 04:08:07 EST
On 10.10.2024 15:20, Nuno Sá wrote:
> On Tue, 2024-10-08 at 17:43 +0200, Angelo Dureghello wrote:
> > From: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> >
> > Extend AXI-DAC backend with new features required to interface
> > to the ad3552r DAC. Mainly, a new compatible string is added to
> > support the ad3552r-axi DAC IP, very similar to the generic DAC
> > IP but with some customizations to work with the ad3552r.
> >
> > Then, a serie of generic functions has been added to match with
> > ad3552r needs. Function names has been kept generic as much as
> > possible, to allow re-utilization from other frontend drivers.
> >
> > Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> > ---
>
> Just some minor stuff. Not seeing any fundamental issue with this patch.
>
> > drivers/iio/dac/adi-axi-dac.c | 285 ++++++++++++++++++++++++++++++++++++++++-
> > -
> > 1 file changed, 274 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> > index 04193a98616e..e43d0ecccb50 100644
> > --- a/drivers/iio/dac/adi-axi-dac.c
> > +++ b/drivers/iio/dac/adi-axi-dac.c
> > @@ -46,9 +46,28 @@
> > #define AXI_DAC_CNTRL_1_REG 0x0044
> > #define AXI_DAC_CNTRL_1_SYNC BIT(0)
> > #define AXI_DAC_CNTRL_2_REG 0x0048
> > +#define AXI_DAC_CNTRL_2_SDR_DDR_N BIT(16)
> > +#define AXI_DAC_CNTRL_2_SYMB_8B BIT(14)
> > #define ADI_DAC_CNTRL_2_R1_MODE BIT(5)
> > +#define AXI_DAC_CNTRL_2_UNSIGNED_DATA BIT(4)
> > +#define AXI_DAC_STATUS_1_REG 0x0054
> > +#define AXI_DAC_STATUS_2_REG 0x0058
> > #define AXI_DAC_DRP_STATUS_REG 0x0074
> > #define AXI_DAC_DRP_STATUS_DRP_LOCKED BIT(17)
> > +#define AXI_DAC_CUSTOM_RD_REG 0x0080
> > +#define AXI_DAC_CUSTOM_WR_REG 0x0084
> > +#define AXI_DAC_CUSTOM_WR_DATA_8 GENMASK(23, 16)
> > +#define AXI_DAC_CUSTOM_WR_DATA_16 GENMASK(23, 8)
> > +#define AXI_DAC_UI_STATUS_REG 0x0088
> > +#define AXI_DAC_UI_STATUS_IF_BUSY BIT(4)
> > +#define AXI_DAC_CUSTOM_CTRL_REG 0x008C
> > +#define AXI_DAC_CUSTOM_CTRL_ADDRESS GENMASK(31, 24)
> > +#define AXI_DAC_CUSTOM_CTRL_SYNCED_TRANSFER BIT(2)
> > +#define AXI_DAC_CUSTOM_CTRL_STREAM BIT(1)
> > +#define AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA BIT(0)
> > +
> > +#define
> > AXI_DAC_STREAM_ENABLE (AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA | \
> > + AXI_DAC_CUSTOM_CTRL_STREAM)
> >
> > /* DAC Channel controls */
> > #define AXI_DAC_CHAN_CNTRL_1_REG(c) (0x0400 + (c) * 0x40)
> > @@ -63,12 +82,27 @@
> > #define AXI_DAC_CHAN_CNTRL_7_REG(c) (0x0418 + (c) * 0x40)
> > #define AXI_DAC_CHAN_CNTRL_7_DATA_SEL GENMASK(3, 0)
> >
> > +#define AXI_DAC_RD_ADDR(x) (BIT(7) | (x))
> > +
> > /* 360 degrees in rad */
> > #define AXI_DAC_2_PI_MEGA 6283190
> >
> > enum {
> > AXI_DAC_DATA_INTERNAL_TONE,
> > AXI_DAC_DATA_DMA = 2,
> > + AXI_DAC_DATA_INTERNAL_RAMP_16BIT = 11,
> > +};
> > +
> > +enum {
> > + AXI_DAC_BUS_TYPE_NONE,
> > + AXI_DAC_BUS_TYPE_DDR_QSPI,
> > +};
>
> Do we still need the above?
>
> > +
> > +struct axi_dac_info {
> > + unsigned int version;
> > + const struct iio_backend_info *backend_info;
> > + bool bus_controller;
> > + bool has_dac_clk;
> > };
> >
> > struct axi_dac_state {
> > @@ -79,9 +113,12 @@ struct axi_dac_state {
> > * data/variables.
> > */
> > struct mutex lock;
> > + const struct axi_dac_info *info;
> > + struct clk *clk;
>
> Is it used?
>
> > u64 dac_clk;
> > u32 reg_config;
> > bool int_tone;
> > + int dac_clk_rate;
> > };
> >
> > static int axi_dac_enable(struct iio_backend *back)
> > @@ -471,6 +508,11 @@ static int axi_dac_data_source_set(struct iio_backend
> > *back, unsigned int chan,
> > AXI_DAC_CHAN_CNTRL_7_REG(chan),
> > AXI_DAC_CHAN_CNTRL_7_DATA_SEL,
> > AXI_DAC_DATA_DMA);
> > + case IIO_BACKEND_INTERNAL_RAMP_16BIT:
> > + return regmap_update_bits(st->regmap,
> > + AXI_DAC_CHAN_CNTRL_7_REG(chan),
> > + AXI_DAC_CHAN_CNTRL_7_DATA_SEL,
> > + AXI_DAC_DATA_INTERNAL_RAMP_16BIT);
> > default:
> > return -EINVAL;
> > }
> > @@ -528,6 +570,186 @@ static int axi_dac_reg_access(struct iio_backend *back,
> > unsigned int reg,
> > return regmap_write(st->regmap, reg, writeval);
> > }
> >
> > +static int axi_dac_ddr_enable(struct iio_backend *back)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > +
> > + return regmap_clear_bits(st->regmap, AXI_DAC_CNTRL_2_REG,
> > + AXI_DAC_CNTRL_2_SDR_DDR_N);
> > +}
> > +
> > +static int axi_dac_ddr_disable(struct iio_backend *back)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > +
> > + return regmap_set_bits(st->regmap, AXI_DAC_CNTRL_2_REG,
> > + AXI_DAC_CNTRL_2_SDR_DDR_N);
> > +}
> > +
> > +static int axi_dac_data_stream_enable(struct iio_backend *back)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > +
> > + return regmap_set_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_STREAM_ENABLE);
> > +}
> > +
> > +static int axi_dac_data_stream_disable(struct iio_backend *back)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > +
> > + return regmap_clear_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_STREAM_ENABLE);
> > +}
> > +
> > +static int axi_dac_data_transfer_addr(struct iio_backend *back, u32 address)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > +
>
> We could add some validation for address with FIELD_MAX()
>
> > + /*
> > + * Sample register address, when the DAC is configured, or stream
> > + * start address when the FSM is in stream state.
> > + */
> > + return regmap_update_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_CUSTOM_CTRL_ADDRESS,
> > + FIELD_PREP(AXI_DAC_CUSTOM_CTRL_ADDRESS,
> > + address));
> > +}
> > +
> > +static int axi_dac_data_format_set(struct iio_backend *back, unsigned int ch,
> > + const struct iio_backend_data_fmt *data)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > + int err;
> >
>
> Not sure if I mentioned it already but please use 'ret' so it's consistent with
> what we have. But for this function, see below
>
> > + switch (data->type) {
> > + case IIO_BACKEND_DATA_UNSIGNED:
> > + err = regmap_clear_bits(st->regmap, AXI_DAC_CNTRL_2_REG,
> > + AXI_DAC_CNTRL_2_UNSIGNED_DATA);
> > + if (err)
> > + return err;
> > + break;
> return regmap_clear_bits();
> > + default:
> > + return -EINVAL;
> > + }
> > +
> > + return 0;
>
> remove the above...
>
> > +}
> > +
> > +static int axi_dac_read_raw(struct iio_backend *back,
> > + struct iio_chan_spec const *chan,
> > + int *val, int *val2, long mask)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > + int err;
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_FREQUENCY: {
> > + int reg;
>
> I would just declare it at top scope and remove {}. Otherwise...
> > +
> > + if (!st->info->has_dac_clk)
> > + return -EOPNOTSUPP;
> > +
> > + /*
> > + * As from ad3552r AXI IP documentation,
> > + * returning the SCLK depending on the stream mode.
> > + */
> > + err = regmap_read(st->regmap, AXI_DAC_CUSTOM_CTRL_REG, ®);
> > + if (err)
> > + return err;
> > +
> > + if (reg & AXI_DAC_CUSTOM_CTRL_STREAM)
> > + *val = st->dac_clk_rate / 2;
> > + else
> > + *val = st->dac_clk_rate / 8;
> > +
> > + return IIO_VAL_INT;
> > + }
>
> ... does not look good
>
> > + default:
> > + return -EINVAL;
> > + }
> > +}
> > +
> > +static int axi_dac_bus_reg_write(struct iio_backend *back, u32 reg, u32 val,
> > + size_t data_size)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > + int ret;
> > + u32 ival;
> > +
> > + if (data_size == 2)
>
> nit: sizeof(u16)
>
> > + ival = FIELD_PREP(AXI_DAC_CUSTOM_WR_DATA_16, val);
> > + else
> > + ival = FIELD_PREP(AXI_DAC_CUSTOM_WR_DATA_8, val);
> > +
> > + ret = regmap_write(st->regmap, AXI_DAC_CUSTOM_WR_REG, ival);
> > + if (ret)
> > + return ret;
> > +
> > + /*
> > + * Both REG_CNTRL_2 and AXI_DAC_CNTRL_DATA_WR need to know
> > + * the data size. So keeping data size control here only,
> > + * since data size is mandatory for the current transfer.
> > + * DDR state handled separately by specific backend calls,
> > + * generally all raw register writes are SDR.
> > + */
> > + if (data_size == 1)
> > + ret = regmap_set_bits(st->regmap, AXI_DAC_CNTRL_2_REG,
> > + AXI_DAC_CNTRL_2_SYMB_8B);
> > + else
> > + ret = regmap_clear_bits(st->regmap, AXI_DAC_CNTRL_2_REG,
> > + AXI_DAC_CNTRL_2_SYMB_8B);
> > + if (ret)
> > + return ret;
> > +
> > + ret = regmap_update_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_CUSTOM_CTRL_ADDRESS,
> > + FIELD_PREP(AXI_DAC_CUSTOM_CTRL_ADDRESS,
> > reg));
> > + if (ret)
> > + return ret;
> > +
> > + ret = regmap_update_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA,
> > + AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA);
> > + if (ret)
> > + return ret;
> > +
> > + ret = regmap_read_poll_timeout(st->regmap,
> > + AXI_DAC_CUSTOM_CTRL_REG, ival,
> > + ival &
> > AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA,
> > + 10, 100 * KILO);
> > + if (ret)
> > + return ret;
> > +
> > + return regmap_clear_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> > + AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA);
> > +}
> > +
> > +static int axi_dac_bus_reg_read(struct iio_backend *back, u32 reg, u32 *val,
> > + size_t data_size)
> > +{
> > + struct axi_dac_state *st = iio_backend_get_priv(back);
> > + int ret;
> > + u32 ival;
> > +
> > + /*
> > + * SPI, we write with read flag, then we read just at the AXI
> > + * io address space to get data read.
> > + */
> > + ret = axi_dac_bus_reg_write(back, AXI_DAC_RD_ADDR(reg), 0,
> > data_size);
> > + if (ret)
> > + return ret;
> > +
> > + ret = regmap_read_poll_timeout(st->regmap, AXI_DAC_UI_STATUS_REG,
> > ival,
> > + FIELD_GET(AXI_DAC_UI_STATUS_IF_BUSY, ival) !=
> > + AXI_DAC_UI_STATUS_IF_BUSY,
> > + 10, 100);
> > + if (ret)
> > + return ret;
> > +
> > + return regmap_read(st->regmap, AXI_DAC_CUSTOM_RD_REG, val);
> > +}
> > +
> > static const struct iio_backend_ops axi_dac_generic_ops = {
> > .enable = axi_dac_enable,
> > .disable = axi_dac_disable,
> > @@ -541,11 +763,29 @@ static const struct iio_backend_ops axi_dac_generic_ops
> > = {
> > .debugfs_reg_access = iio_backend_debugfs_ptr(axi_dac_reg_access),
> > };
> >
> > +static const struct iio_backend_ops axi_ad3552r_ops = {
> > + .enable = axi_dac_enable,
> > + .read_raw = axi_dac_read_raw,
> > + .request_buffer = axi_dac_request_buffer,
> > + .data_source_set = axi_dac_data_source_set,
> > + .ddr_enable = axi_dac_ddr_enable,
> > + .ddr_disable = axi_dac_ddr_disable,
> > + .data_stream_enable = axi_dac_data_stream_enable,
> > + .data_stream_disable = axi_dac_data_stream_disable,
> > + .data_format_set = axi_dac_data_format_set,
> > + .data_transfer_addr = axi_dac_data_transfer_addr,
> > +};
> > +
> > static const struct iio_backend_info axi_dac_generic = {
> > .name = "axi-dac",
> > .ops = &axi_dac_generic_ops,
> > };
> >
> > +static const struct iio_backend_info axi_ad3552r = {
> > + .name = "axi-ad3552r",
> > + .ops = &axi_ad3552r_ops,
> > +};
> > +
> > static const struct regmap_config axi_dac_regmap_config = {
> > .val_bits = 32,
> > .reg_bits = 32,
> > @@ -555,7 +795,6 @@ static const struct regmap_config axi_dac_regmap_config =
> > {
> >
> > static int axi_dac_probe(struct platform_device *pdev)
> > {
> > - const unsigned int *expected_ver;
> > struct axi_dac_state *st;
> > void __iomem *base;
> > unsigned int ver;
> > @@ -566,15 +805,26 @@ static int axi_dac_probe(struct platform_device *pdev)
> > if (!st)
> > return -ENOMEM;
> >
> > - expected_ver = device_get_match_data(&pdev->dev);
> > - if (!expected_ver)
> > + st->info = device_get_match_data(&pdev->dev);
> > + if (!st->info)
> > return -ENODEV;
> >
> > - clk = devm_clk_get_enabled(&pdev->dev, NULL);
> > + clk = devm_clk_get_enabled(&pdev->dev, "s_axi_aclk");
> > if (IS_ERR(clk))
> > return dev_err_probe(&pdev->dev, PTR_ERR(clk),
> > "failed to get clock\n");
> >
> > + if (st->info->has_dac_clk) {
> > + struct clk *dac_clk;
> > +
> > + dac_clk = devm_clk_get_enabled(&pdev->dev, "dac_clk");
> > + if (IS_ERR(dac_clk))
> > + return dev_err_probe(&pdev->dev, PTR_ERR(dac_clk),
> > + "failed to get dac_clk
> > clock\n");
> > +
> > + st->dac_clk_rate = clk_get_rate(dac_clk);
> > + }
> > +
> > base = devm_platform_ioremap_resource(pdev, 0);
> > if (IS_ERR(base))
> > return PTR_ERR(base);
> > @@ -598,12 +848,13 @@ static int axi_dac_probe(struct platform_device *pdev)
> > if (ret)
> > return ret;
> >
> > - if (ADI_AXI_PCORE_VER_MAJOR(ver) !=
> > ADI_AXI_PCORE_VER_MAJOR(*expected_ver)) {
> > + if (ADI_AXI_PCORE_VER_MAJOR(ver) !=
> > + ADI_AXI_PCORE_VER_MAJOR(st->info->version)) {
> > dev_err(&pdev->dev,
> > "Major version mismatch. Expected %d.%.2d.%c,
> > Reported %d.%.2d.%c\n",
> > - ADI_AXI_PCORE_VER_MAJOR(*expected_ver),
> > - ADI_AXI_PCORE_VER_MINOR(*expected_ver),
> > - ADI_AXI_PCORE_VER_PATCH(*expected_ver),
> > + ADI_AXI_PCORE_VER_MAJOR(st->info->version),
> > + ADI_AXI_PCORE_VER_MINOR(st->info->version),
> > + ADI_AXI_PCORE_VER_PATCH(st->info->version),
> > ADI_AXI_PCORE_VER_MAJOR(ver),
> > ADI_AXI_PCORE_VER_MINOR(ver),
> > ADI_AXI_PCORE_VER_PATCH(ver));
> > @@ -629,7 +880,8 @@ static int axi_dac_probe(struct platform_device *pdev)
> > return ret;
> >
> > mutex_init(&st->lock);
> > - ret = devm_iio_backend_register(&pdev->dev, &axi_dac_generic, st);
> > +
> > + ret = devm_iio_backend_register(&pdev->dev, st->info->backend_info,
> > st);
> > if (ret)
> > return dev_err_probe(&pdev->dev, ret,
> > "failed to register iio backend\n");
> > @@ -642,10 +894,21 @@ static int axi_dac_probe(struct platform_device *pdev)
> > return 0;
> > }
> >
> > -static unsigned int axi_dac_9_1_b_info = ADI_AXI_PCORE_VER(9, 1, 'b');
> > +static const struct axi_dac_info dac_generic = {
> > + .version = ADI_AXI_PCORE_VER(9, 1, 'b'),
> > + .backend_info = &axi_dac_generic,
> > +};
> > +
> > +static const struct axi_dac_info dac_ad3552r = {
> > + .version = ADI_AXI_PCORE_VER(9, 1, 'b'),
> > + .backend_info = &axi_ad3552r,
> > + .bus_controller = true,
>
> Do we still need bus_controller?
actually still using it to create devices subnodes.
Will move it to the last patch.
>
> - Nuno Sá
>
>
Regards,
angelo