From a515d64885054603fd33a8b31d380b4fbad0f6eb Mon Sep 17 00:00:00 2001 From: Artur Rojek Date: Sat, 27 Jul 2019 21:59:40 +0200 Subject: [PATCH] IIO: Ingenic JZ47xx: Add support for JZ4770 SoC ADC. Add support for the ADC hardware present on Ingenic JZ4770 SoC. Signed-off-by: Artur Rojek Tested-by: Paul Cercueil Signed-off-by: Jonathan Cameron --- drivers/iio/adc/ingenic-adc.c | 149 +++++++++++++++++++++++++++++----- 1 file changed, 127 insertions(+), 22 deletions(-) diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c index e234970b7150..7a53c2f8d438 100644 --- a/drivers/iio/adc/ingenic-adc.c +++ b/drivers/iio/adc/ingenic-adc.c @@ -25,9 +25,13 @@ #define JZ_ADC_REG_ADSDAT 0x20 #define JZ_ADC_REG_ADCLK 0x28 +#define JZ_ADC_REG_ENABLE_PD BIT(7) +#define JZ_ADC_REG_CFG_AUX_MD (BIT(0) | BIT(1)) #define JZ_ADC_REG_CFG_BAT_MD BIT(4) #define JZ_ADC_REG_ADCLK_CLKDIV_LSB 0 -#define JZ_ADC_REG_ADCLK_CLKDIV10US_LSB 16 +#define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB 16 +#define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB 8 +#define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB 16 #define JZ_ADC_AUX_VREF 3300 #define JZ_ADC_AUX_VREF_BITS 12 @@ -37,6 +41,8 @@ #define JZ4725B_ADC_BATTERY_HIGH_VREF_BITS 10 #define JZ4740_ADC_BATTERY_HIGH_VREF (7500 * 0.986) #define JZ4740_ADC_BATTERY_HIGH_VREF_BITS 12 +#define JZ4770_ADC_BATTERY_VREF 6600 +#define JZ4770_ADC_BATTERY_VREF_BITS 12 struct ingenic_adc; @@ -47,6 +53,8 @@ struct ingenic_adc_soc_data { size_t battery_raw_avail_size; const int *battery_scale_avail; size_t battery_scale_avail_size; + unsigned int battery_vref_mode: 1; + unsigned int has_aux2: 1; int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc); }; @@ -54,6 +62,7 @@ struct ingenic_adc { void __iomem *base; struct clk *clk; struct mutex lock; + struct mutex aux_lock; const struct ingenic_adc_soc_data *soc_data; bool low_vref_mode; }; @@ -120,6 +129,8 @@ static int ingenic_adc_write_raw(struct iio_dev *iio_dev, case IIO_CHAN_INFO_SCALE: switch (chan->channel) { case INGENIC_ADC_BATTERY: + if (!adc->soc_data->battery_vref_mode) + return -EINVAL; if (val > JZ_ADC_BATTERY_LOW_VREF) { ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_BAT_MD, @@ -158,6 +169,14 @@ static const int jz4740_adc_battery_scale_avail[] = { JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS, }; +static const int jz4770_adc_battery_raw_avail[] = { + 0, 1, (1 << JZ4770_ADC_BATTERY_VREF_BITS) - 1, +}; + +static const int jz4770_adc_battery_scale_avail[] = { + JZ4770_ADC_BATTERY_VREF, JZ4770_ADC_BATTERY_VREF_BITS, +}; + static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc) { struct clk *parent_clk; @@ -187,7 +206,45 @@ static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc) /* We also need a divider that produces a 10us clock. */ div_10us = DIV_ROUND_UP(rate, 100000); - writel(((div_10us - 1) << JZ_ADC_REG_ADCLK_CLKDIV10US_LSB) | + writel(((div_10us - 1) << JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB) | + (div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB, + adc->base + JZ_ADC_REG_ADCLK); + + return 0; +} + +static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc) +{ + struct clk *parent_clk; + unsigned long parent_rate, rate; + unsigned int div_main, div_ms, div_10us; + + parent_clk = clk_get_parent(adc->clk); + if (!parent_clk) { + dev_err(dev, "ADC clock has no parent\n"); + return -ENODEV; + } + parent_rate = clk_get_rate(parent_clk); + + /* + * The JZ4770 ADC works at 20 kHz to 200 kHz. + * We pick the highest rate possible. + */ + div_main = DIV_ROUND_UP(parent_rate, 200000); + div_main = clamp(div_main, 1u, 256u); + rate = parent_rate / div_main; + if (rate < 20000 || rate > 200000) { + dev_err(dev, "No valid divider for ADC main clock\n"); + return -EINVAL; + } + + /* We also need a divider that produces a 10us clock. */ + div_10us = DIV_ROUND_UP(rate, 10000); + /* And another, which produces a 1ms clock. */ + div_ms = DIV_ROUND_UP(rate, 1000); + + writel(((div_ms - 1) << JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB) | + ((div_10us - 1) << JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB) | (div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB, adc->base + JZ_ADC_REG_ADCLK); @@ -201,6 +258,8 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = { .battery_raw_avail_size = ARRAY_SIZE(jz4725b_adc_battery_raw_avail), .battery_scale_avail = jz4725b_adc_battery_scale_avail, .battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail), + .battery_vref_mode = true, + .has_aux2 = false, .init_clk_div = jz4725b_adc_init_clk_div, }; @@ -211,9 +270,23 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = { .battery_raw_avail_size = ARRAY_SIZE(jz4740_adc_battery_raw_avail), .battery_scale_avail = jz4740_adc_battery_scale_avail, .battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail), + .battery_vref_mode = true, + .has_aux2 = false, .init_clk_div = NULL, /* no ADCLK register on JZ4740 */ }; +static const struct ingenic_adc_soc_data jz4770_adc_soc_data = { + .battery_high_vref = JZ4770_ADC_BATTERY_VREF, + .battery_high_vref_bits = JZ4770_ADC_BATTERY_VREF_BITS, + .battery_raw_avail = jz4770_adc_battery_raw_avail, + .battery_raw_avail_size = ARRAY_SIZE(jz4770_adc_battery_raw_avail), + .battery_scale_avail = jz4770_adc_battery_scale_avail, + .battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail), + .battery_vref_mode = false, + .has_aux2 = true, + .init_clk_div = jz4770_adc_init_clk_div, +}; + static int ingenic_adc_read_avail(struct iio_dev *iio_dev, struct iio_chan_spec const *chan, const int **vals, @@ -239,6 +312,42 @@ static int ingenic_adc_read_avail(struct iio_dev *iio_dev, }; } +static int ingenic_adc_read_chan_info_raw(struct ingenic_adc *adc, + struct iio_chan_spec const *chan, + int *val) +{ + int bit, ret, engine = (chan->channel == INGENIC_ADC_BATTERY); + + /* We cannot sample AUX/AUX2 in parallel. */ + mutex_lock(&adc->aux_lock); + if (adc->soc_data->has_aux2 && engine == 0) { + bit = BIT(chan->channel == INGENIC_ADC_AUX2); + ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, bit); + } + + clk_enable(adc->clk); + ret = ingenic_adc_capture(adc, engine); + if (ret) + goto out; + + switch (chan->channel) { + case INGENIC_ADC_AUX: + case INGENIC_ADC_AUX2: + *val = readw(adc->base + JZ_ADC_REG_ADSDAT); + break; + case INGENIC_ADC_BATTERY: + *val = readw(adc->base + JZ_ADC_REG_ADBDAT); + break; + } + + ret = IIO_VAL_INT; +out: + clk_disable(adc->clk); + mutex_unlock(&adc->aux_lock); + + return ret; +} + static int ingenic_adc_read_raw(struct iio_dev *iio_dev, struct iio_chan_spec const *chan, int *val, @@ -246,32 +355,14 @@ static int ingenic_adc_read_raw(struct iio_dev *iio_dev, long m) { struct ingenic_adc *adc = iio_priv(iio_dev); - int ret; switch (m) { case IIO_CHAN_INFO_RAW: - clk_enable(adc->clk); - ret = ingenic_adc_capture(adc, chan->channel); - if (ret) { - clk_disable(adc->clk); - return ret; - } - - switch (chan->channel) { - case INGENIC_ADC_AUX: - *val = readw(adc->base + JZ_ADC_REG_ADSDAT); - break; - case INGENIC_ADC_BATTERY: - *val = readw(adc->base + JZ_ADC_REG_ADBDAT); - break; - } - - clk_disable(adc->clk); - - return IIO_VAL_INT; + return ingenic_adc_read_chan_info_raw(adc, chan, val); case IIO_CHAN_INFO_SCALE: switch (chan->channel) { case INGENIC_ADC_AUX: + case INGENIC_ADC_AUX2: *val = JZ_ADC_AUX_VREF; *val2 = JZ_ADC_AUX_VREF_BITS; break; @@ -322,6 +413,14 @@ static const struct iio_chan_spec ingenic_channels[] = { .indexed = 1, .channel = INGENIC_ADC_BATTERY, }, + { /* Must always be last in the array. */ + .extend_name = "aux2", + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .indexed = 1, + .channel = INGENIC_ADC_AUX2, + }, }; static int ingenic_adc_probe(struct platform_device *pdev) @@ -343,6 +442,7 @@ static int ingenic_adc_probe(struct platform_device *pdev) adc = iio_priv(iio_dev); mutex_init(&adc->lock); + mutex_init(&adc->aux_lock); adc->soc_data = soc_data; mem_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -374,6 +474,7 @@ static int ingenic_adc_probe(struct platform_device *pdev) /* Put hardware in a known passive state. */ writeb(0x00, adc->base + JZ_ADC_REG_ENABLE); writeb(0xff, adc->base + JZ_ADC_REG_CTRL); + usleep_range(2000, 3000); /* Must wait at least 2ms. */ clk_disable(adc->clk); ret = devm_add_action_or_reset(dev, ingenic_adc_clk_cleanup, adc->clk); @@ -387,6 +488,9 @@ static int ingenic_adc_probe(struct platform_device *pdev) iio_dev->modes = INDIO_DIRECT_MODE; iio_dev->channels = ingenic_channels; iio_dev->num_channels = ARRAY_SIZE(ingenic_channels); + /* Remove AUX2 from the list of supported channels. */ + if (!adc->soc_data->has_aux2) + iio_dev->num_channels -= 1; iio_dev->info = &ingenic_adc_info; ret = devm_iio_device_register(dev, iio_dev); @@ -400,6 +504,7 @@ static int ingenic_adc_probe(struct platform_device *pdev) static const struct of_device_id ingenic_adc_of_match[] = { { .compatible = "ingenic,jz4725b-adc", .data = &jz4725b_adc_soc_data, }, { .compatible = "ingenic,jz4740-adc", .data = &jz4740_adc_soc_data, }, + { .compatible = "ingenic,jz4770-adc", .data = &jz4770_adc_soc_data, }, { }, }; MODULE_DEVICE_TABLE(of, ingenic_adc_of_match);