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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/input/touchscreen/ti_am335x_tsc.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/touchscreen/ti_am335x_tsc.c')
-rw-r--r-- | drivers/input/touchscreen/ti_am335x_tsc.c | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c new file mode 100644 index 000000000..f2fb6a9a1 --- /dev/null +++ b/drivers/input/touchscreen/ti_am335x_tsc.c @@ -0,0 +1,567 @@ +/* + * TI Touch Screen driver + * + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/input.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/sort.h> +#include <linux/pm_wakeirq.h> + +#include <linux/mfd/ti_am335x_tscadc.h> + +#define ADCFSM_STEPID 0x10 +#define SEQ_SETTLE 275 +#define MAX_12BIT ((1 << 12) - 1) + +#define TSC_IRQENB_MASK (IRQENB_FIFO0THRES | IRQENB_EOS | IRQENB_HW_PEN) + +static const int config_pins[] = { + STEPCONFIG_XPP, + STEPCONFIG_XNN, + STEPCONFIG_YPP, + STEPCONFIG_YNN, +}; + +struct titsc { + struct input_dev *input; + struct ti_tscadc_dev *mfd_tscadc; + struct device *dev; + unsigned int irq; + unsigned int wires; + unsigned int x_plate_resistance; + bool pen_down; + int coordinate_readouts; + u32 config_inp[4]; + u32 bit_xp, bit_xn, bit_yp, bit_yn; + u32 inp_xp, inp_xn, inp_yp, inp_yn; + u32 step_mask; + u32 charge_delay; +}; + +static unsigned int titsc_readl(struct titsc *ts, unsigned int reg) +{ + return readl(ts->mfd_tscadc->tscadc_base + reg); +} + +static void titsc_writel(struct titsc *tsc, unsigned int reg, + unsigned int val) +{ + writel(val, tsc->mfd_tscadc->tscadc_base + reg); +} + +static int titsc_config_wires(struct titsc *ts_dev) +{ + u32 analog_line[4]; + u32 wire_order[4]; + int i, bit_cfg; + + for (i = 0; i < 4; i++) { + /* + * Get the order in which TSC wires are attached + * w.r.t. each of the analog input lines on the EVM. + */ + analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4; + wire_order[i] = ts_dev->config_inp[i] & 0x0F; + if (WARN_ON(analog_line[i] > 7)) + return -EINVAL; + if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins))) + return -EINVAL; + } + + for (i = 0; i < 4; i++) { + int an_line; + int wi_order; + + an_line = analog_line[i]; + wi_order = wire_order[i]; + bit_cfg = config_pins[wi_order]; + if (bit_cfg == 0) + return -EINVAL; + switch (wi_order) { + case 0: + ts_dev->bit_xp = bit_cfg; + ts_dev->inp_xp = an_line; + break; + + case 1: + ts_dev->bit_xn = bit_cfg; + ts_dev->inp_xn = an_line; + break; + + case 2: + ts_dev->bit_yp = bit_cfg; + ts_dev->inp_yp = an_line; + break; + case 3: + ts_dev->bit_yn = bit_cfg; + ts_dev->inp_yn = an_line; + break; + } + } + return 0; +} + +static void titsc_step_config(struct titsc *ts_dev) +{ + unsigned int config; + int i, n; + int end_step, first_step, tsc_steps; + u32 stepenable; + + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_AVG_16 | ts_dev->bit_xp | + STEPCONFIG_INM_ADCREFM; + switch (ts_dev->wires) { + case 4: + config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn; + break; + case 5: + config |= ts_dev->bit_yn | + STEPCONFIG_INP_AN4 | ts_dev->bit_xn | + ts_dev->bit_yp; + break; + case 8: + config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn; + break; + } + + tsc_steps = ts_dev->coordinate_readouts * 2 + 2; + first_step = TOTAL_STEPS - tsc_steps; + /* Steps 16 to 16-coordinate_readouts is for X */ + end_step = first_step + tsc_steps; + n = 0; + for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) { + titsc_writel(ts_dev, REG_STEPCONFIG(i), config); + titsc_writel(ts_dev, REG_STEPDELAY(i), + n++ == 0 ? STEPCONFIG_OPENDLY : 0); + } + + config = 0; + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_AVG_16 | ts_dev->bit_yn | + STEPCONFIG_INM_ADCREFM; + switch (ts_dev->wires) { + case 4: + config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp); + break; + case 5: + config |= ts_dev->bit_xp | STEPCONFIG_INP_AN4 | + STEPCONFIG_XNP | STEPCONFIG_YPN; + break; + case 8: + config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp); + break; + } + + /* 1 ... coordinate_readouts is for Y */ + end_step = first_step + ts_dev->coordinate_readouts; + n = 0; + for (i = first_step; i < end_step; i++) { + titsc_writel(ts_dev, REG_STEPCONFIG(i), config); + titsc_writel(ts_dev, REG_STEPDELAY(i), + n++ == 0 ? STEPCONFIG_OPENDLY : 0); + } + + /* Make CHARGECONFIG same as IDLECONFIG */ + + config = titsc_readl(ts_dev, REG_IDLECONFIG); + titsc_writel(ts_dev, REG_CHARGECONFIG, config); + titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay); + + /* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */ + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_AVG_16 | ts_dev->bit_yp | + ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM | + STEPCONFIG_INP(ts_dev->inp_xp); + titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config); + titsc_writel(ts_dev, REG_STEPDELAY(end_step), + STEPCONFIG_OPENDLY); + + end_step++; + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_AVG_16 | ts_dev->bit_yp | + ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM | + STEPCONFIG_INP(ts_dev->inp_yn); + titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config); + titsc_writel(ts_dev, REG_STEPDELAY(end_step), + STEPCONFIG_OPENDLY); + + /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */ + stepenable = 1; + for (i = 0; i < tsc_steps; i++) + stepenable |= 1 << (first_step + i + 1); + + ts_dev->step_mask = stepenable; + am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask); +} + +static int titsc_cmp_coord(const void *a, const void *b) +{ + return *(int *)a - *(int *)b; +} + +static void titsc_read_coordinates(struct titsc *ts_dev, + u32 *x, u32 *y, u32 *z1, u32 *z2) +{ + unsigned int yvals[7], xvals[7]; + unsigned int i, xsum = 0, ysum = 0; + unsigned int creads = ts_dev->coordinate_readouts; + + for (i = 0; i < creads; i++) { + yvals[i] = titsc_readl(ts_dev, REG_FIFO0); + yvals[i] &= 0xfff; + } + + *z1 = titsc_readl(ts_dev, REG_FIFO0); + *z1 &= 0xfff; + *z2 = titsc_readl(ts_dev, REG_FIFO0); + *z2 &= 0xfff; + + for (i = 0; i < creads; i++) { + xvals[i] = titsc_readl(ts_dev, REG_FIFO0); + xvals[i] &= 0xfff; + } + + /* + * If co-ordinates readouts is less than 4 then + * report the average. In case of 4 or more + * readouts, sort the co-ordinate samples, drop + * min and max values and report the average of + * remaining values. + */ + if (creads <= 3) { + for (i = 0; i < creads; i++) { + ysum += yvals[i]; + xsum += xvals[i]; + } + ysum /= creads; + xsum /= creads; + } else { + sort(yvals, creads, sizeof(unsigned int), + titsc_cmp_coord, NULL); + sort(xvals, creads, sizeof(unsigned int), + titsc_cmp_coord, NULL); + for (i = 1; i < creads - 1; i++) { + ysum += yvals[i]; + xsum += xvals[i]; + } + ysum /= creads - 2; + xsum /= creads - 2; + } + *y = ysum; + *x = xsum; +} + +static irqreturn_t titsc_irq(int irq, void *dev) +{ + struct titsc *ts_dev = dev; + struct input_dev *input_dev = ts_dev->input; + unsigned int fsm, status, irqclr = 0; + unsigned int x = 0, y = 0; + unsigned int z1, z2, z; + + status = titsc_readl(ts_dev, REG_RAWIRQSTATUS); + if (status & IRQENB_HW_PEN) { + ts_dev->pen_down = true; + irqclr |= IRQENB_HW_PEN; + pm_stay_awake(ts_dev->dev); + } + + if (status & IRQENB_PENUP) { + fsm = titsc_readl(ts_dev, REG_ADCFSM); + if (fsm == ADCFSM_STEPID) { + ts_dev->pen_down = false; + input_report_key(input_dev, BTN_TOUCH, 0); + input_report_abs(input_dev, ABS_PRESSURE, 0); + input_sync(input_dev); + pm_relax(ts_dev->dev); + } else { + ts_dev->pen_down = true; + } + irqclr |= IRQENB_PENUP; + } + + if (status & IRQENB_EOS) + irqclr |= IRQENB_EOS; + + /* + * ADC and touchscreen share the IRQ line. + * FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only + */ + if (status & IRQENB_FIFO0THRES) { + + titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2); + + if (ts_dev->pen_down && z1 != 0 && z2 != 0) { + /* + * Calculate pressure using formula + * Resistance(touch) = x plate resistance * + * x position/4096 * ((z2 / z1) - 1) + */ + z = z1 - z2; + z *= x; + z *= ts_dev->x_plate_resistance; + z /= z2; + z = (z + 2047) >> 12; + + if (z <= MAX_12BIT) { + input_report_abs(input_dev, ABS_X, x); + input_report_abs(input_dev, ABS_Y, y); + input_report_abs(input_dev, ABS_PRESSURE, z); + input_report_key(input_dev, BTN_TOUCH, 1); + input_sync(input_dev); + } + } + irqclr |= IRQENB_FIFO0THRES; + } + if (irqclr) { + titsc_writel(ts_dev, REG_IRQSTATUS, irqclr); + if (status & IRQENB_EOS) + am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, + ts_dev->step_mask); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static int titsc_parse_dt(struct platform_device *pdev, + struct titsc *ts_dev) +{ + struct device_node *node = pdev->dev.of_node; + int err; + + if (!node) + return -EINVAL; + + err = of_property_read_u32(node, "ti,wires", &ts_dev->wires); + if (err < 0) + return err; + switch (ts_dev->wires) { + case 4: + case 5: + case 8: + break; + default: + return -EINVAL; + } + + err = of_property_read_u32(node, "ti,x-plate-resistance", + &ts_dev->x_plate_resistance); + if (err < 0) + return err; + + /* + * Try with the new binding first. If it fails, try again with + * bogus, miss-spelled version. + */ + err = of_property_read_u32(node, "ti,coordinate-readouts", + &ts_dev->coordinate_readouts); + if (err < 0) { + dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n"); + err = of_property_read_u32(node, "ti,coordiante-readouts", + &ts_dev->coordinate_readouts); + } + + if (err < 0) + return err; + + if (ts_dev->coordinate_readouts <= 0) { + dev_warn(&pdev->dev, + "invalid co-ordinate readouts, resetting it to 5\n"); + ts_dev->coordinate_readouts = 5; + } + + err = of_property_read_u32(node, "ti,charge-delay", + &ts_dev->charge_delay); + /* + * If ti,charge-delay value is not specified, then use + * CHARGEDLY_OPENDLY as the default value. + */ + if (err < 0) { + ts_dev->charge_delay = CHARGEDLY_OPENDLY; + dev_warn(&pdev->dev, "ti,charge-delay not specified\n"); + } + + return of_property_read_u32_array(node, "ti,wire-config", + ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp)); +} + +/* + * The functions for inserting/removing driver as a module. + */ + +static int titsc_probe(struct platform_device *pdev) +{ + struct titsc *ts_dev; + struct input_dev *input_dev; + struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev); + int err; + + /* Allocate memory for device */ + ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL); + input_dev = input_allocate_device(); + if (!ts_dev || !input_dev) { + dev_err(&pdev->dev, "failed to allocate memory.\n"); + err = -ENOMEM; + goto err_free_mem; + } + + tscadc_dev->tsc = ts_dev; + ts_dev->mfd_tscadc = tscadc_dev; + ts_dev->input = input_dev; + ts_dev->irq = tscadc_dev->irq; + ts_dev->dev = &pdev->dev; + + err = titsc_parse_dt(pdev, ts_dev); + if (err) { + dev_err(&pdev->dev, "Could not find valid DT data.\n"); + goto err_free_mem; + } + + err = request_irq(ts_dev->irq, titsc_irq, + IRQF_SHARED, pdev->dev.driver->name, ts_dev); + if (err) { + dev_err(&pdev->dev, "failed to allocate irq.\n"); + goto err_free_mem; + } + + device_init_wakeup(&pdev->dev, true); + err = dev_pm_set_wake_irq(&pdev->dev, ts_dev->irq); + if (err) + dev_err(&pdev->dev, "irq wake enable failed.\n"); + + titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK); + titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES); + titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS); + err = titsc_config_wires(ts_dev); + if (err) { + dev_err(&pdev->dev, "wrong i/p wire configuration\n"); + goto err_free_irq; + } + titsc_step_config(ts_dev); + titsc_writel(ts_dev, REG_FIFO0THR, + ts_dev->coordinate_readouts * 2 + 2 - 1); + + input_dev->name = "ti-tsc"; + input_dev->dev.parent = &pdev->dev; + + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + + input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0); + + /* register to the input system */ + err = input_register_device(input_dev); + if (err) + goto err_free_irq; + + platform_set_drvdata(pdev, ts_dev); + return 0; + +err_free_irq: + dev_pm_clear_wake_irq(&pdev->dev); + device_init_wakeup(&pdev->dev, false); + free_irq(ts_dev->irq, ts_dev); +err_free_mem: + input_free_device(input_dev); + kfree(ts_dev); + return err; +} + +static int titsc_remove(struct platform_device *pdev) +{ + struct titsc *ts_dev = platform_get_drvdata(pdev); + u32 steps; + + dev_pm_clear_wake_irq(&pdev->dev); + device_init_wakeup(&pdev->dev, false); + free_irq(ts_dev->irq, ts_dev); + + /* total steps followed by the enable mask */ + steps = 2 * ts_dev->coordinate_readouts + 2; + steps = (1 << steps) - 1; + am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps); + + input_unregister_device(ts_dev->input); + + kfree(ts_dev); + return 0; +} + +static int __maybe_unused titsc_suspend(struct device *dev) +{ + struct titsc *ts_dev = dev_get_drvdata(dev); + unsigned int idle; + + if (device_may_wakeup(dev)) { + titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK); + idle = titsc_readl(ts_dev, REG_IRQENABLE); + titsc_writel(ts_dev, REG_IRQENABLE, + (idle | IRQENB_HW_PEN)); + titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB); + } + return 0; +} + +static int __maybe_unused titsc_resume(struct device *dev) +{ + struct titsc *ts_dev = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) { + titsc_writel(ts_dev, REG_IRQWAKEUP, + 0x00); + titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN); + pm_relax(dev); + } + titsc_step_config(ts_dev); + titsc_writel(ts_dev, REG_FIFO0THR, + ts_dev->coordinate_readouts * 2 + 2 - 1); + return 0; +} + +static SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume); + +static const struct of_device_id ti_tsc_dt_ids[] = { + { .compatible = "ti,am3359-tsc", }, + { } +}; +MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids); + +static struct platform_driver ti_tsc_driver = { + .probe = titsc_probe, + .remove = titsc_remove, + .driver = { + .name = "TI-am335x-tsc", + .pm = &titsc_pm_ops, + .of_match_table = ti_tsc_dt_ids, + }, +}; +module_platform_driver(ti_tsc_driver); + +MODULE_DESCRIPTION("TI touchscreen controller driver"); +MODULE_AUTHOR("Rachna Patil <rachna@ti.com>"); +MODULE_LICENSE("GPL"); |