am335x触摸屏驱动ti_am335x_tsc.c

/* * 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) 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; 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; /*add by lc 2018-10-16 * 触摸点值偶然随机偏离。解决办法，每检测到3次上报1次，只上报第2次，1、3次的数据抛弃。 * cnt：检测次数计数器； * x/y/z：记录第2次数据，上报的就是这组数据。 */ u32 cnt; u32 x; u32 y; u32 z; }; 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; int end_step, first_step, tsc_steps; u32 stepenable; config = STEPCONFIG_MODE_HWSYNC | STEPCONFIG_AVG_16 | ts_dev->bit_xp; 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; 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), STEPCONFIG_OPENDLY); } 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; for (i = first_step; i < end_step; i++) { titsc_writel(ts_dev, REG_STEPCONFIG(i), config); titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY); } /* 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_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_clean_fifo(struct titsc *ts_dev) { int i; unsigned int creads = (ts_dev->coordinate_readouts<<1) + 2; for (i = 0; i < creads; i++) { titsc_readl(ts_dev, REG_FIFO0); } } 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 1 /*相当于延时*/ { int i; for(i=0; i<20; i++) titsc_readl(ts_dev, REG_ADCFSM); } #endif if (status & IRQENB_HW_PEN) { ts_dev->pen_down = true; irqclr |= IRQENB_HW_PEN; pm_stay_awake(ts_dev->mfd_tscadc->dev); } if (status & IRQENB_PENUP) { fsm = titsc_readl(ts_dev, REG_ADCFSM); if (fsm == ADCFSM_STEPID || status==0x600) { 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->mfd_tscadc->dev); } else { ts_dev->pen_down = true;