diff options
Diffstat (limited to 'drivers/staging/iio/adc/mxs-lradc.c')
| -rw-r--r-- | drivers/staging/iio/adc/mxs-lradc.c | 207 |
1 files changed, 105 insertions, 102 deletions
diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c index d9d6fad7cb00..816174388f13 100644 --- a/drivers/staging/iio/adc/mxs-lradc.c +++ b/drivers/staging/iio/adc/mxs-lradc.c @@ -214,11 +214,17 @@ struct mxs_lradc { unsigned long is_divided; /* - * Touchscreen LRADC channels receives a private slot in the CTRL4 - * register, the slot #7. Therefore only 7 slots instead of 8 in the - * CTRL4 register can be mapped to LRADC channels when using the - * touchscreen. - * + * When the touchscreen is enabled, we give it two private virtual + * channels: #6 and #7. This means that only 6 virtual channels (instead + * of 8) will be available for buffered capture. + */ +#define TOUCHSCREEN_VCHANNEL1 7 +#define TOUCHSCREEN_VCHANNEL2 6 +#define BUFFER_VCHANS_LIMITED 0x3f +#define BUFFER_VCHANS_ALL 0xff + u8 buffer_vchans; + + /* * Furthermore, certain LRADC channels are shared between touchscreen * and/or touch-buttons and generic LRADC block. Therefore when using * either of these, these channels are not available for the regular @@ -342,6 +348,9 @@ struct mxs_lradc { #define LRADC_CTRL4 0x140 #define LRADC_CTRL4_LRADCSELECT_MASK(n) (0xf << ((n) * 4)) #define LRADC_CTRL4_LRADCSELECT_OFFSET(n) ((n) * 4) +#define LRADC_CTRL4_LRADCSELECT(n, x) \ + (((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \ + LRADC_CTRL4_LRADCSELECT_MASK(n)) #define LRADC_RESOLUTION 12 #define LRADC_SINGLE_SAMPLE_MASK ((1 << LRADC_RESOLUTION) - 1) @@ -416,6 +425,14 @@ static bool mxs_lradc_check_touch_event(struct mxs_lradc *lradc) LRADC_STATUS_TOUCH_DETECT_RAW); } +static void mxs_lradc_map_channel(struct mxs_lradc *lradc, unsigned vch, + unsigned ch) +{ + mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(vch), + LRADC_CTRL4); + mxs_lradc_reg_set(lradc, LRADC_CTRL4_LRADCSELECT(vch, ch), LRADC_CTRL4); +} + static void mxs_lradc_setup_ts_channel(struct mxs_lradc *lradc, unsigned ch) { /* @@ -450,12 +467,8 @@ static void mxs_lradc_setup_ts_channel(struct mxs_lradc *lradc, unsigned ch) LRADC_DELAY_DELAY(lradc->over_sample_delay - 1), LRADC_DELAY(3)); - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(2) | - LRADC_CTRL1_LRADC_IRQ(3) | LRADC_CTRL1_LRADC_IRQ(4) | - LRADC_CTRL1_LRADC_IRQ(5), LRADC_CTRL1); + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch), LRADC_CTRL1); - /* wake us again, when the complete conversion is done */ - mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(ch), LRADC_CTRL1); /* * after changing the touchscreen plates setting * the signals need some initial time to settle. Start the @@ -509,12 +522,8 @@ static void mxs_lradc_setup_ts_pressure(struct mxs_lradc *lradc, unsigned ch1, LRADC_DELAY_DELAY(lradc->over_sample_delay - 1), LRADC_DELAY(3)); - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(2) | - LRADC_CTRL1_LRADC_IRQ(3) | LRADC_CTRL1_LRADC_IRQ(4) | - LRADC_CTRL1_LRADC_IRQ(5), LRADC_CTRL1); + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch2), LRADC_CTRL1); - /* wake us again, when the conversions are done */ - mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(ch2), LRADC_CTRL1); /* * after changing the touchscreen plates setting * the signals need some initial time to settle. Start the @@ -580,36 +589,6 @@ static unsigned mxs_lradc_read_ts_pressure(struct mxs_lradc *lradc, #define TS_CH_XM 4 #define TS_CH_YM 5 -static int mxs_lradc_read_ts_channel(struct mxs_lradc *lradc) -{ - u32 reg; - int val; - - reg = readl(lradc->base + LRADC_CTRL1); - - /* only channels 3 to 5 are of interest here */ - if (reg & LRADC_CTRL1_LRADC_IRQ(TS_CH_YP)) { - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(TS_CH_YP) | - LRADC_CTRL1_LRADC_IRQ(TS_CH_YP), LRADC_CTRL1); - val = mxs_lradc_read_raw_channel(lradc, TS_CH_YP); - } else if (reg & LRADC_CTRL1_LRADC_IRQ(TS_CH_XM)) { - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(TS_CH_XM) | - LRADC_CTRL1_LRADC_IRQ(TS_CH_XM), LRADC_CTRL1); - val = mxs_lradc_read_raw_channel(lradc, TS_CH_XM); - } else if (reg & LRADC_CTRL1_LRADC_IRQ(TS_CH_YM)) { - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(TS_CH_YM) | - LRADC_CTRL1_LRADC_IRQ(TS_CH_YM), LRADC_CTRL1); - val = mxs_lradc_read_raw_channel(lradc, TS_CH_YM); - } else { - return -EIO; - } - - mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2)); - mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3)); - - return val; -} - /* * YP(open)--+-------------+ * | |--+ @@ -653,7 +632,8 @@ static void mxs_lradc_prepare_x_pos(struct mxs_lradc *lradc) mxs_lradc_reg_set(lradc, mxs_lradc_drive_x_plate(lradc), LRADC_CTRL0); lradc->cur_plate = LRADC_SAMPLE_X; - mxs_lradc_setup_ts_channel(lradc, TS_CH_YP); + mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YP); + mxs_lradc_setup_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1); } /* @@ -674,7 +654,8 @@ static void mxs_lradc_prepare_y_pos(struct mxs_lradc *lradc) mxs_lradc_reg_set(lradc, mxs_lradc_drive_y_plate(lradc), LRADC_CTRL0); lradc->cur_plate = LRADC_SAMPLE_Y; - mxs_lradc_setup_ts_channel(lradc, TS_CH_XM); + mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_XM); + mxs_lradc_setup_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1); } /* @@ -695,7 +676,10 @@ static void mxs_lradc_prepare_pressure(struct mxs_lradc *lradc) mxs_lradc_reg_set(lradc, mxs_lradc_drive_pressure(lradc), LRADC_CTRL0); lradc->cur_plate = LRADC_SAMPLE_PRESSURE; - mxs_lradc_setup_ts_pressure(lradc, TS_CH_XP, TS_CH_YM); + mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YM); + mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL2, TS_CH_XP); + mxs_lradc_setup_ts_pressure(lradc, TOUCHSCREEN_VCHANNEL2, + TOUCHSCREEN_VCHANNEL1); } static void mxs_lradc_enable_touch_detection(struct mxs_lradc *lradc) @@ -708,6 +692,19 @@ static void mxs_lradc_enable_touch_detection(struct mxs_lradc *lradc) mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1); } +static void mxs_lradc_start_touch_event(struct mxs_lradc *lradc) +{ + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, + LRADC_CTRL1); + mxs_lradc_reg_set(lradc, + LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1), LRADC_CTRL1); + /* + * start with the Y-pos, because it uses nearly the same plate + * settings like the touch detection + */ + mxs_lradc_prepare_y_pos(lradc); +} + static void mxs_lradc_report_ts_event(struct mxs_lradc *lradc) { input_report_abs(lradc->ts_input, ABS_X, lradc->ts_x_pos); @@ -725,10 +722,12 @@ static void mxs_lradc_complete_touch_event(struct mxs_lradc *lradc) * start a dummy conversion to burn time to settle the signals * note: we are not interested in the conversion's value */ - mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(5)); - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(5), LRADC_CTRL1); - mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(5), LRADC_CTRL1); - mxs_lradc_reg_wrt(lradc, LRADC_DELAY_TRIGGER(1 << 5) | + mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(TOUCHSCREEN_VCHANNEL1)); + mxs_lradc_reg_clear(lradc, + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) | + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2), LRADC_CTRL1); + mxs_lradc_reg_wrt(lradc, + LRADC_DELAY_TRIGGER(1 << TOUCHSCREEN_VCHANNEL1) | LRADC_DELAY_KICK | LRADC_DELAY_DELAY(10), /* waste 5 ms */ LRADC_DELAY(2)); } @@ -760,59 +759,45 @@ static void mxs_lradc_finish_touch_event(struct mxs_lradc *lradc, bool valid) /* if it is released, wait for the next touch via IRQ */ lradc->cur_plate = LRADC_TOUCH; - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ, LRADC_CTRL1); + mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2)); + mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3)); + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ | + LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) | + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1), LRADC_CTRL1); mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1); } /* touchscreen's state machine */ static void mxs_lradc_handle_touch(struct mxs_lradc *lradc) { - int val; - switch (lradc->cur_plate) { case LRADC_TOUCH: - /* - * start with the Y-pos, because it uses nearly the same plate - * settings like the touch detection - */ - if (mxs_lradc_check_touch_event(lradc)) { - mxs_lradc_reg_clear(lradc, - LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, - LRADC_CTRL1); - mxs_lradc_prepare_y_pos(lradc); - } + if (mxs_lradc_check_touch_event(lradc)) + mxs_lradc_start_touch_event(lradc); mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ, LRADC_CTRL1); return; case LRADC_SAMPLE_Y: - val = mxs_lradc_read_ts_channel(lradc); - if (val < 0) { - mxs_lradc_enable_touch_detection(lradc); /* re-start */ - return; - } - lradc->ts_y_pos = val; + lradc->ts_y_pos = mxs_lradc_read_raw_channel(lradc, + TOUCHSCREEN_VCHANNEL1); mxs_lradc_prepare_x_pos(lradc); return; case LRADC_SAMPLE_X: - val = mxs_lradc_read_ts_channel(lradc); - if (val < 0) { - mxs_lradc_enable_touch_detection(lradc); /* re-start */ - return; - } - lradc->ts_x_pos = val; + lradc->ts_x_pos = mxs_lradc_read_raw_channel(lradc, + TOUCHSCREEN_VCHANNEL1); mxs_lradc_prepare_pressure(lradc); return; case LRADC_SAMPLE_PRESSURE: - lradc->ts_pressure = - mxs_lradc_read_ts_pressure(lradc, TS_CH_XP, TS_CH_YM); + lradc->ts_pressure = mxs_lradc_read_ts_pressure(lradc, + TOUCHSCREEN_VCHANNEL2, + TOUCHSCREEN_VCHANNEL1); mxs_lradc_complete_touch_event(lradc); return; case LRADC_SAMPLE_VALID: - val = mxs_lradc_read_ts_channel(lradc); /* ignore the value */ mxs_lradc_finish_touch_event(lradc, 1); break; } @@ -844,9 +829,9 @@ static int mxs_lradc_read_single(struct iio_dev *iio_dev, int chan, int *val) * used if doing raw sampling. */ if (lradc->soc == IMX28_LRADC) - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK, + mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1); - mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0); + mxs_lradc_reg_clear(lradc, 0x1, LRADC_CTRL0); /* Enable / disable the divider per requirement */ if (test_bit(chan, &lradc->is_divided)) @@ -1090,9 +1075,8 @@ static void mxs_lradc_disable_ts(struct mxs_lradc *lradc) { /* stop all interrupts from firing */ mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN | - LRADC_CTRL1_LRADC_IRQ_EN(2) | LRADC_CTRL1_LRADC_IRQ_EN(3) | - LRADC_CTRL1_LRADC_IRQ_EN(4) | LRADC_CTRL1_LRADC_IRQ_EN(5), - LRADC_CTRL1); + LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) | + LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL2), LRADC_CTRL1); /* Power-down touchscreen touch-detect circuitry. */ mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0); @@ -1158,26 +1142,31 @@ static irqreturn_t mxs_lradc_handle_irq(int irq, void *data) struct iio_dev *iio = data; struct mxs_lradc *lradc = iio_priv(iio); unsigned long reg = readl(lradc->base + LRADC_CTRL1); + uint32_t clr_irq = mxs_lradc_irq_mask(lradc); const uint32_t ts_irq_mask = LRADC_CTRL1_TOUCH_DETECT_IRQ | - LRADC_CTRL1_LRADC_IRQ(2) | - LRADC_CTRL1_LRADC_IRQ(3) | - LRADC_CTRL1_LRADC_IRQ(4) | - LRADC_CTRL1_LRADC_IRQ(5); + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) | + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2); if (!(reg & mxs_lradc_irq_mask(lradc))) return IRQ_NONE; - if (lradc->use_touchscreen && (reg & ts_irq_mask)) + if (lradc->use_touchscreen && (reg & ts_irq_mask)) { mxs_lradc_handle_touch(lradc); - if (iio_buffer_enabled(iio)) - iio_trigger_poll(iio->trig); - else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) + /* Make sure we don't clear the next conversion's interrupt. */ + clr_irq &= ~(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) | + LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2)); + } + + if (iio_buffer_enabled(iio)) { + if (reg & lradc->buffer_vchans) + iio_trigger_poll(iio->trig); + } else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) { complete(&lradc->completion); + } - mxs_lradc_reg_clear(lradc, reg & mxs_lradc_irq_mask(lradc), - LRADC_CTRL1); + mxs_lradc_reg_clear(lradc, reg & clr_irq, LRADC_CTRL1); return IRQ_HANDLED; } @@ -1289,9 +1278,10 @@ static int mxs_lradc_buffer_preenable(struct iio_dev *iio) } if (lradc->soc == IMX28_LRADC) - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK, - LRADC_CTRL1); - mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0); + mxs_lradc_reg_clear(lradc, + lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET, + LRADC_CTRL1); + mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0); for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) { ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs); @@ -1324,10 +1314,11 @@ static int mxs_lradc_buffer_postdisable(struct iio_dev *iio) mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK, LRADC_DELAY(0)); - mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0); + mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0); if (lradc->soc == IMX28_LRADC) - mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK, - LRADC_CTRL1); + mxs_lradc_reg_clear(lradc, + lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET, + LRADC_CTRL1); kfree(lradc->buffer); mutex_unlock(&lradc->lock); @@ -1353,7 +1344,7 @@ static bool mxs_lradc_validate_scan_mask(struct iio_dev *iio, if (lradc->use_touchbutton) rsvd_chans++; if (lradc->use_touchscreen) - rsvd_chans++; + rsvd_chans += 2; /* Test for attempts to map channels with special mode of operation. */ if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS)) @@ -1413,6 +1404,13 @@ static const struct iio_chan_spec mxs_lradc_chan_spec[] = { .channel = 8, .scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,}, }, + /* Hidden channel to keep indexes */ + { + .type = IIO_TEMP, + .indexed = 1, + .scan_index = -1, + .channel = 9, + }, MXS_ADC_CHAN(10, IIO_VOLTAGE), /* VDDIO */ MXS_ADC_CHAN(11, IIO_VOLTAGE), /* VTH */ MXS_ADC_CHAN(12, IIO_VOLTAGE), /* VDDA */ @@ -1583,6 +1581,11 @@ static int mxs_lradc_probe(struct platform_device *pdev) touch_ret = mxs_lradc_probe_touchscreen(lradc, node); + if (touch_ret == 0) + lradc->buffer_vchans = BUFFER_VCHANS_LIMITED; + else + lradc->buffer_vchans = BUFFER_VCHANS_ALL; + /* Grab all IRQ sources */ for (i = 0; i < of_cfg->irq_count; i++) { lradc->irq[i] = platform_get_irq(pdev, i); |