| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Hui Wang | 2079 | 31.96% | 1 | 1.30% |
| David Brownell | 1524 | 23.43% | 7 | 9.09% |
| Imre Deak | 727 | 11.18% | 11 | 14.29% |
| Daniel Mack | 646 | 9.93% | 1 | 1.30% |
| Anatolij Gustschin | 423 | 6.50% | 2 | 2.60% |
| Dmitry Torokhov | 253 | 3.89% | 8 | 10.39% |
| Eric Miao | 165 | 2.54% | 2 | 2.60% |
| Semih Hazar | 130 | 2.00% | 2 | 2.60% |
| Grazvydas Ignotas | 111 | 1.71% | 1 | 1.30% |
| Guenter Roeck | 99 | 1.52% | 1 | 1.30% |
| Michael Roth | 56 | 0.86% | 3 | 3.90% |
| Ranjith Lohithakshan | 54 | 0.83% | 1 | 1.30% |
| Mark Brown | 47 | 0.72% | 3 | 3.90% |
| Alexander Stein | 35 | 0.54% | 3 | 3.90% |
| Igor Grinberg | 29 | 0.45% | 3 | 3.90% |
| Vitaly Wool | 18 | 0.28% | 1 | 1.30% |
| Andrey Gelman | 17 | 0.26% | 1 | 1.30% |
| JJ Ding | 12 | 0.18% | 1 | 1.30% |
| Michael Hennerich | 11 | 0.17% | 1 | 1.30% |
| Kevin Hilman | 10 | 0.15% | 1 | 1.30% |
| Pramod Gurav | 8 | 0.12% | 1 | 1.30% |
| Joe Rouvier | 6 | 0.09% | 1 | 1.30% |
| Harvey Harrison | 6 | 0.09% | 2 | 2.60% |
| David Jander | 5 | 0.08% | 1 | 1.30% |
| Anton Vorontsov | 5 | 0.08% | 1 | 1.30% |
| Jingoo Han | 4 | 0.06% | 2 | 2.60% |
| Marc Pignat | 4 | 0.06% | 1 | 1.30% |
| Andrew Morton | 3 | 0.05% | 2 | 2.60% |
| Paul Gortmaker | 3 | 0.05% | 1 | 1.30% |
| Nicolas Ferre | 2 | 0.03% | 1 | 1.30% |
| Fabio Estevam | 2 | 0.03% | 1 | 1.30% |
| Hans-Christian Noren Egtvedt | 2 | 0.03% | 1 | 1.30% |
| Arvind Yadav | 2 | 0.03% | 1 | 1.30% |
| Axel Lin | 1 | 0.02% | 1 | 1.30% |
| Adam Buchbinder | 1 | 0.02% | 1 | 1.30% |
| Pavel Machek | 1 | 0.02% | 1 | 1.30% |
| Christoph Lameter | 1 | 0.02% | 1 | 1.30% |
| Javier Martinez Canillas | 1 | 0.02% | 1 | 1.30% |
| Kay Sievers | 1 | 0.02% | 1 | 1.30% |
| Tony Jones | 1 | 0.02% | 1 | 1.30% |
| Total | 6505 | 77 |
/* * ADS7846 based touchscreen and sensor driver * * Copyright (c) 2005 David Brownell * Copyright (c) 2006 Nokia Corporation * Various changes: Imre Deak <imre.deak@nokia.com> * * Using code from: * - corgi_ts.c * Copyright (C) 2004-2005 Richard Purdie * - omap_ts.[hc], ads7846.h, ts_osk.c * Copyright (C) 2002 MontaVista Software * Copyright (C) 2004 Texas Instruments * Copyright (C) 2005 Dirk Behme * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/types.h> #include <linux/hwmon.h> #include <linux/err.h> #include <linux/sched.h> #include <linux/delay.h> #include <linux/input.h> #include <linux/interrupt.h> #include <linux/slab.h> #include <linux/pm.h> #include <linux/of.h> #include <linux/of_gpio.h> #include <linux/of_device.h> #include <linux/gpio.h> #include <linux/spi/spi.h> #include <linux/spi/ads7846.h> #include <linux/regulator/consumer.h> #include <linux/module.h> #include <asm/irq.h> /* * This code has been heavily tested on a Nokia 770, and lightly * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). * TSC2046 is just newer ads7846 silicon. * Support for ads7843 tested on Atmel at91sam926x-EK. * Support for ads7845 has only been stubbed in. * Support for Analog Devices AD7873 and AD7843 tested. * * IRQ handling needs a workaround because of a shortcoming in handling * edge triggered IRQs on some platforms like the OMAP1/2. These * platforms don't handle the ARM lazy IRQ disabling properly, thus we * have to maintain our own SW IRQ disabled status. This should be * removed as soon as the affected platform's IRQ handling is fixed. * * App note sbaa036 talks in more detail about accurate sampling... * that ought to help in situations like LCDs inducing noise (which * can also be helped by using synch signals) and more generally. * This driver tries to utilize the measures described in the app * note. The strength of filtering can be set in the board-* specific * files. */ #define TS_POLL_DELAY 1 /* ms delay before the first sample */ #define TS_POLL_PERIOD 5 /* ms delay between samples */ /* this driver doesn't aim at the peak continuous sample rate */ #define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) struct ts_event { /* * For portability, we can't read 12 bit values using SPI (which * would make the controller deliver them as native byte order u16 * with msbs zeroed). Instead, we read them as two 8-bit values, * *** WHICH NEED BYTESWAPPING *** and range adjustment. */ u16 x; u16 y; u16 z1, z2; bool ignore; u8 x_buf[3]; u8 y_buf[3]; }; /* * We allocate this separately to avoid cache line sharing issues when * driver is used with DMA-based SPI controllers (like atmel_spi) on * systems where main memory is not DMA-coherent (most non-x86 boards). */ struct ads7846_packet { u8 read_x, read_y, read_z1, read_z2, pwrdown; u16 dummy; /* for the pwrdown read */ struct ts_event tc; /* for ads7845 with mpc5121 psc spi we use 3-byte buffers */ u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3]; }; struct ads7846 { struct input_dev *input; char phys[32]; char name[32]; struct spi_device *spi; struct regulator *reg; #if IS_ENABLED(CONFIG_HWMON) struct device *hwmon; #endif u16 model; u16 vref_mv; u16 vref_delay_usecs; u16 x_plate_ohms; u16 pressure_max; bool swap_xy; bool use_internal; struct ads7846_packet *packet; struct spi_transfer xfer[18]; struct spi_message msg[5]; int msg_count; wait_queue_head_t wait; bool pendown; int read_cnt; int read_rep; int last_read; u16 debounce_max; u16 debounce_tol; u16 debounce_rep; u16 penirq_recheck_delay_usecs; struct mutex lock; bool stopped; /* P: lock */ bool disabled; /* P: lock */ bool suspended; /* P: lock */ int (*filter)(void *data, int data_idx, int *val); void *filter_data; void (*filter_cleanup)(void *data); int (*get_pendown_state)(void); int gpio_pendown; void (*wait_for_sync)(void); }; /* leave chip selected when we're done, for quicker re-select? */ #if 0 #define CS_CHANGE(xfer) ((xfer).cs_change = 1) #else #define CS_CHANGE(xfer) ((xfer).cs_change = 0) #endif /*--------------------------------------------------------------------------*/ /* The ADS7846 has touchscreen and other sensors. * Earlier ads784x chips are somewhat compatible. */ #define ADS_START (1 << 7) #define ADS_A2A1A0_d_y (1 << 4) /* differential */ #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ #define ADS_A2A1A0_d_x (5 << 4) /* differential */ #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ #define ADS_8_BIT (1 << 3) #define ADS_12_BIT (0 << 3) #define ADS_SER (1 << 2) /* non-differential */ #define ADS_DFR (0 << 2) /* differential */ #define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ #define MAX_12BIT ((1<<12)-1) /* leave ADC powered up (disables penirq) between differential samples */ #define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ | ADS_12_BIT | ADS_DFR | \ (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) #define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) #define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) #define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) #define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) #define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ /* single-ended samples need to first power up reference voltage; * we leave both ADC and VREF powered */ #define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ | ADS_12_BIT | ADS_SER) #define REF_ON (READ_12BIT_DFR(x, 1, 1)) #define REF_OFF (READ_12BIT_DFR(y, 0, 0)) /* Must be called with ts->lock held */ static void ads7846_stop(struct ads7846 *ts) { if (!ts->disabled && !ts->suspended) { /* Signal IRQ thread to stop polling and disable the handler. */ ts->stopped = true; mb(); wake_up(&ts->wait); disable_irq(ts->spi->irq); } } /* Must be called with ts->lock held */ static void ads7846_restart(struct ads7846 *ts) { if (!ts->disabled && !ts->suspended) { /* Tell IRQ thread that it may poll the device. */ ts->stopped = false; mb(); enable_irq(ts->spi->irq); } } /* Must be called with ts->lock held */ static void __ads7846_disable(struct ads7846 *ts) { ads7846_stop(ts); regulator_disable(ts->reg); /* * We know the chip's in low power mode since we always * leave it that way after every request */ } /* Must be called with ts->lock held */ static void __ads7846_enable(struct ads7846 *ts) { int error; error = regulator_enable(ts->reg); if (error != 0) dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error); ads7846_restart(ts); } static void ads7846_disable(struct ads7846 *ts) { mutex_lock(&ts->lock); if (!ts->disabled) { if (!ts->suspended) __ads7846_disable(ts); ts->disabled = true; } mutex_unlock(&ts->lock); } static void ads7846_enable(struct ads7846 *ts) { mutex_lock(&ts->lock); if (ts->disabled) { ts->disabled = false; if (!ts->suspended) __ads7846_enable(ts); } mutex_unlock(&ts->lock); } /*--------------------------------------------------------------------------*/ /* * Non-touchscreen sensors only use single-ended conversions. * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; * ads7846 lets that pin be unconnected, to use internal vREF. */ struct ser_req { u8 ref_on; u8 command; u8 ref_off; u16 scratch; struct spi_message msg; struct spi_transfer xfer[6]; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. */ __be16 sample ____cacheline_aligned; }; struct ads7845_ser_req { u8 command[3]; struct spi_message msg; struct spi_transfer xfer[2]; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. */ u8 sample[3] ____cacheline_aligned; }; static int ads7846_read12_ser(struct device *dev, unsigned command) { struct spi_device *spi = to_spi_device(dev); struct ads7846 *ts = dev_get_drvdata(dev); struct ser_req *req; int status; req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; spi_message_init(&req->msg); /* maybe turn on internal vREF, and let it settle */ if (ts->use_internal) { req->ref_on = REF_ON; req->xfer[0].tx_buf = &req->ref_on; req->xfer[0].len = 1; spi_message_add_tail(&req->xfer[0], &req->msg); req->xfer[1].rx_buf = &req->scratch; req->xfer[1].len = 2; /* for 1uF, settle for 800 usec; no cap, 100 usec. */ req->xfer[1].delay_usecs = ts->vref_delay_usecs; spi_message_add_tail(&req->xfer[1], &req->msg); /* Enable reference voltage */ command |= ADS_PD10_REF_ON; } /* Enable ADC in every case */ command |= ADS_PD10_ADC_ON; /* take sample */ req->command = (u8) command; req->xfer[2].tx_buf = &req->command; req->xfer[2].len = 1; spi_message_add_tail(&req->xfer[2], &req->msg); req->xfer[3].rx_buf = &req->sample; req->xfer[3].len = 2; spi_message_add_tail(&req->xfer[3], &req->msg); /* REVISIT: take a few more samples, and compare ... */ /* converter in low power mode & enable PENIRQ */ req->ref_off = PWRDOWN; req->xfer[4].tx_buf = &req->ref_off; req->xfer[4].len = 1; spi_message_add_tail(&req->xfer[4], &req->msg); req->xfer[5].rx_buf = &req->scratch; req->xfer[5].len = 2; CS_CHANGE(req->xfer[5]); spi_message_add_tail(&req->xfer[5], &req->msg); mutex_lock(&ts->lock); ads7846_stop(ts); status = spi_sync(spi, &req->msg); ads7846_restart(ts); mutex_unlock(&ts->lock); if (status == 0) { /* on-wire is a must-ignore bit, a BE12 value, then padding */ status = be16_to_cpu(req->sample); status = status >> 3; status &= 0x0fff; } kfree(req); return status; } static int ads7845_read12_ser(struct device *dev, unsigned command) { struct spi_device *spi = to_spi_device(dev); struct ads7846 *ts = dev_get_drvdata(dev); struct ads7845_ser_req *req; int status; req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; spi_message_init(&req->msg); req->command[0] = (u8) command; req->xfer[0].tx_buf = req->command; req->xfer[0].rx_buf = req->sample; req->xfer[0].len = 3; spi_message_add_tail(&req->xfer[0], &req->msg); mutex_lock(&ts->lock); ads7846_stop(ts); status = spi_sync(spi, &req->msg); ads7846_restart(ts); mutex_unlock(&ts->lock); if (status == 0) { /* BE12 value, then padding */ status = be16_to_cpu(*((u16 *)&req->sample[1])); status = status >> 3; status &= 0x0fff; } kfree(req); return status; } #if IS_ENABLED(CONFIG_HWMON) #define SHOW(name, var, adjust) static ssize_t \ name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ { \ struct ads7846 *ts = dev_get_drvdata(dev); \ ssize_t v = ads7846_read12_ser(&ts->spi->dev, \ READ_12BIT_SER(var)); \ if (v < 0) \ return v; \ return sprintf(buf, "%u\n", adjust(ts, v)); \ } \ static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); /* Sysfs conventions report temperatures in millidegrees Celsius. * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high * accuracy scheme without calibration data. For now we won't try either; * userspace sees raw sensor values, and must scale/calibrate appropriately. */ static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) { return v; } SHOW(temp0, temp0, null_adjust) /* temp1_input */ SHOW(temp1, temp1, null_adjust) /* temp2_input */ /* sysfs conventions report voltages in millivolts. We can convert voltages * if we know vREF. userspace may need to scale vAUX to match the board's * external resistors; we assume that vBATT only uses the internal ones. */ static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) { unsigned retval = v; /* external resistors may scale vAUX into 0..vREF */ retval *= ts->vref_mv; retval = retval >> 12; return retval; } static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) { unsigned retval = vaux_adjust(ts, v); /* ads7846 has a resistor ladder to scale this signal down */ if (ts->model == 7846) retval *= 4; return retval; } SHOW(in0_input, vaux, vaux_adjust) SHOW(in1_input, vbatt, vbatt_adjust) static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr, int index) { struct device *dev = container_of(kobj, struct device, kobj); struct ads7846 *ts = dev_get_drvdata(dev); if (ts->model == 7843 && index < 2) /* in0, in1 */ return 0; if (ts->model == 7845 && index != 2) /* in0 */ return 0; return attr->mode; } static struct attribute *ads7846_attributes[] = { &dev_attr_temp0.attr, /* 0 */ &dev_attr_temp1.attr, /* 1 */ &dev_attr_in0_input.attr, /* 2 */ &dev_attr_in1_input.attr, /* 3 */ NULL, }; static const struct attribute_group ads7846_attr_group = { .attrs = ads7846_attributes, .is_visible = ads7846_is_visible, }; __ATTRIBUTE_GROUPS(ads7846_attr); static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) { /* hwmon sensors need a reference voltage */ switch (ts->model) { case 7846: if (!ts->vref_mv) { dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); ts->vref_mv = 2500; ts->use_internal = true; } break; case 7845: case 7843: if (!ts->vref_mv) { dev_warn(&spi->dev, "external vREF for ADS%d not specified\n", ts->model); return 0; } break; } ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias, ts, ads7846_attr_groups); return PTR_ERR_OR_ZERO(ts->hwmon); } static void ads784x_hwmon_unregister(struct spi_device *spi, struct ads7846 *ts) { if (ts->hwmon) hwmon_device_unregister(ts->hwmon); } #else static inline int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) { return 0; } static inline void ads784x_hwmon_unregister(struct spi_device *spi, struct ads7846 *ts) { } #endif static ssize_t ads7846_pen_down_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ads7846 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->pendown); } static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); static ssize_t ads7846_disable_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ads7846 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->disabled); } static ssize_t ads7846_disable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ads7846 *ts = dev_get_drvdata(dev); unsigned int i; int err; err = kstrtouint(buf, 10, &i); if (err) return err; if (i) ads7846_disable(ts); else ads7846_enable(ts); return count; } static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); static struct attribute *ads784x_attributes[] = { &dev_attr_pen_down.attr, &dev_attr_disable.attr, NULL, }; static const struct attribute_group ads784x_attr_group = { .attrs = ads784x_attributes, }; /*--------------------------------------------------------------------------*/ static int get_pendown_state(struct ads7846 *ts) { if (ts->get_pendown_state) return ts->get_pendown_state(); return !gpio_get_value(ts->gpio_pendown); } static void null_wait_for_sync(void) { } static int ads7846_debounce_filter(void *ads, int data_idx, int *val) { struct ads7846 *ts = ads; if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { /* Start over collecting consistent readings. */ ts->read_rep = 0; /* * Repeat it, if this was the first read or the read * wasn't consistent enough. */ if (ts->read_cnt < ts->debounce_max) { ts->last_read = *val; ts->read_cnt++; return ADS7846_FILTER_REPEAT; } else { /* * Maximum number of debouncing reached and still * not enough number of consistent readings. Abort * the whole sample, repeat it in the next sampling * period. */ ts->read_cnt = 0; return ADS7846_FILTER_IGNORE; } } else { if (++ts->read_rep > ts->debounce_rep) { /* * Got a good reading for this coordinate, * go for the next one. */ ts->read_cnt = 0; ts->read_rep = 0; return ADS7846_FILTER_OK; } else { /* Read more values that are consistent. */ ts->read_cnt++; return ADS7846_FILTER_REPEAT; } } } static int ads7846_no_filter(void *ads, int data_idx, int *val) { return ADS7846_FILTER_OK; } static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) { int value; struct spi_transfer *t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list); if (ts->model == 7845) { value = be16_to_cpup((__be16 *)&(((char *)t->rx_buf)[1])); } else { /* * adjust: on-wire is a must-ignore bit, a BE12 value, then * padding; built from two 8 bit values written msb-first. */ value = be16_to_cpup((__be16 *)t->rx_buf); } /* enforce ADC output is 12 bits width */ return (value >> 3) & 0xfff; } static void ads7846_update_value(struct spi_message *m, int val) { struct spi_transfer *t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list); *(u16 *)t->rx_buf = val; } static void ads7846_read_state(struct ads7846 *ts) { struct ads7846_packet *packet = ts->packet; struct spi_message *m; int msg_idx = 0; int val; int action; int error; while (msg_idx < ts->msg_count) { ts->wait_for_sync(); m = &ts->msg[msg_idx]; error = spi_sync(ts->spi, m); if (error) { dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); packet->tc.ignore = true; return; } /* * Last message is power down request, no need to convert * or filter the value. */ if (msg_idx < ts->msg_count - 1) { val = ads7846_get_value(ts, m); action = ts->filter(ts->filter_data, msg_idx, &val); switch (action) { case ADS7846_FILTER_REPEAT: continue; case ADS7846_FILTER_IGNORE: packet->tc.ignore = true; msg_idx = ts->msg_count - 1; continue; case ADS7846_FILTER_OK: ads7846_update_value(m, val); packet->tc.ignore = false; msg_idx++; break; default: BUG(); } } else { msg_idx++; } } } static void ads7846_report_state(struct ads7846 *ts) { struct ads7846_packet *packet = ts->packet; unsigned int Rt; u16 x, y, z1, z2; /* * ads7846_get_value() does in-place conversion (including byte swap) * from on-the-wire format as part of debouncing to get stable * readings. */ if (ts->model == 7845) { x = *(u16 *)packet->tc.x_buf; y = *(u16 *)packet->tc.y_buf; z1 = 0; z2 = 0; } else { x = packet->tc.x; y = packet->tc.y; z1 = packet->tc.z1; z2 = packet->tc.z2; } /* range filtering */ if (x == MAX_12BIT) x = 0; if (ts->model == 7843) { Rt = ts->pressure_max / 2; } else if (ts->model == 7845) { if (get_pendown_state(ts)) Rt = ts->pressure_max / 2; else Rt = 0; dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt); } else if (likely(x && z1)) { /* compute touch pressure resistance using equation #2 */ Rt = z2; Rt -= z1; Rt *= x; Rt *= ts->x_plate_ohms; Rt /= z1; Rt = (Rt + 2047) >> 12; } else { Rt = 0; } /* * Sample found inconsistent by debouncing or pressure is beyond * the maximum. Don't report it to user space, repeat at least * once more the measurement */ if (packet->tc.ignore || Rt > ts->pressure_max) { dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", packet->tc.ignore, Rt); return; } /* * Maybe check the pendown state before reporting. This discards * false readings when the pen is lifted. */ if (ts->penirq_recheck_delay_usecs) { udelay(ts->penirq_recheck_delay_usecs); if (!get_pendown_state(ts)) Rt = 0; } /* * NOTE: We can't rely on the pressure to determine the pen down * state, even this controller has a pressure sensor. The pressure * value can fluctuate for quite a while after lifting the pen and * in some cases may not even settle at the expected value. * * The only safe way to check for the pen up condition is in the * timer by reading the pen signal state (it's a GPIO _and_ IRQ). */ if (Rt) { struct input_dev *input = ts->input; if (ts->swap_xy) swap(x, y); if (!ts->pendown) { input_report_key(input, BTN_TOUCH, 1); ts->pendown = true; dev_vdbg(&ts->spi->dev, "DOWN\n"); } input_report_abs(input, ABS_X, x); input_report_abs(input, ABS_Y, y); input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); input_sync(input); dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); } } static irqreturn_t ads7846_hard_irq(int irq, void *handle) { struct ads7846 *ts = handle; return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; } static irqreturn_t ads7846_irq(int irq, void *handle) { struct ads7846 *ts = handle; /* Start with a small delay before checking pendown state */ msleep(TS_POLL_DELAY); while (!ts->stopped && get_pendown_state(ts)) { /* pen is down, continue with the measurement */ ads7846_read_state(ts); if (!ts->stopped) ads7846_report_state(ts); wait_event_timeout(ts->wait, ts->stopped, msecs_to_jiffies(TS_POLL_PERIOD)); } if (ts->pendown && !ts->stopped) { struct input_dev *input = ts->input; input_report_key(input, BTN_TOUCH, 0); input_report_abs(input, ABS_PRESSURE, 0); input_sync(input); ts->pendown = false; dev_vdbg(&ts->spi->dev, "UP\n"); } return IRQ_HANDLED; } static int __maybe_unused ads7846_suspend(struct device *dev) { struct ads7846 *ts = dev_get_drvdata(dev); mutex_lock(&ts->lock); if (!ts->suspended) { if (!ts->disabled) __ads7846_disable(ts); if (device_may_wakeup(&ts->spi->dev)) enable_irq_wake(ts->spi->irq); ts->suspended = true; } mutex_unlock(&ts->lock); return 0; } static int __maybe_unused ads7846_resume(struct device *dev) { struct ads7846 *ts = dev_get_drvdata(dev); mutex_lock(&ts->lock); if (ts->suspended) { ts->suspended = false; if (device_may_wakeup(&ts->spi->dev)) disable_irq_wake(ts->spi->irq); if (!ts->disabled) __ads7846_enable(ts); } mutex_unlock(&ts->lock); return 0; } static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); static int ads7846_setup_pendown(struct spi_device *spi, struct ads7846 *ts, const struct ads7846_platform_data *pdata) { int err; /* * REVISIT when the irq can be triggered active-low, or if for some * reason the touchscreen isn't hooked up, we don't need to access * the pendown state. */ if (pdata->get_pendown_state) { ts->get_pendown_state = pdata->get_pendown_state; } else if (gpio_is_valid(pdata->gpio_pendown)) { err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN, "ads7846_pendown"); if (err) { dev_err(&spi->dev, "failed to request/setup pendown GPIO%d: %d\n", pdata->gpio_pendown, err); return err; } ts->gpio_pendown = pdata->gpio_pendown; if (pdata->gpio_pendown_debounce) gpio_set_debounce(pdata->gpio_pendown, pdata->gpio_pendown_debounce); } else { dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); return -EINVAL; } return 0; } /* * Set up the transfers to read touchscreen state; this assumes we * use formula #2 for pressure, not #3. */ static void ads7846_setup_spi_msg(struct ads7846 *ts, const struct ads7846_platform_data *pdata) { struct spi_message *m = &ts->msg[0]; struct spi_transfer *x = ts->xfer; struct ads7846_packet *packet = ts->packet; int vref = pdata->keep_vref_on; if (ts->model == 7873) { /* * The AD7873 is almost identical to the ADS7846 * keep VREF off during differential/ratiometric * conversion modes. */ ts->model = 7846; vref = 0; } ts->msg_count = 1; spi_message_init(m); m->context = ts; if (ts->model == 7845) { packet->read_y_cmd[0] = READ_Y(vref); packet->read_y_cmd[1] = 0; packet->read_y_cmd[2] = 0; x->tx_buf = &packet->read_y_cmd[0]; x->rx_buf = &packet->tc.y_buf[0]; x->len = 3; spi_message_add_tail(x, m); } else { /* y- still on; turn on only y+ (and ADC) */ packet->read_y = READ_Y(vref); x->tx_buf = &packet->read_y; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.y; x->len = 2; spi_message_add_tail(x, m); } /* * The first sample after switching drivers can be low quality; * optionally discard it, using a second one after the signals * have had enough time to stabilize. */ if (pdata->settle_delay_usecs) { x->delay_usecs = pdata->settle_delay_usecs; x++; x->tx_buf = &packet->read_y; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.y; x->len = 2; spi_message_add_tail(x, m); } ts->msg_count++; m++; spi_message_init(m); m->context = ts; if (ts->model == 7845) { x++; packet->read_x_cmd[0] = READ_X(vref); packet->read_x_cmd[1] = 0; packet->read_x_cmd[2] = 0; x->tx_buf = &packet->read_x_cmd[0]; x->rx_buf = &packet->tc.x_buf[0]; x->len = 3; spi_message_add_tail(x, m); } else { /* turn y- off, x+ on, then leave in lowpower */ x++; packet->read_x = READ_X(vref); x->tx_buf = &packet->read_x; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.x; x->len = 2; spi_message_add_tail(x, m); } /* ... maybe discard first sample ... */ if (pdata->settle_delay_usecs) { x->delay_usecs = pdata->settle_delay_usecs; x++; x->tx_buf = &packet->read_x; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.x; x->len = 2; spi_message_add_tail(x, m); } /* turn y+ off, x- on; we'll use formula #2 */ if (ts->model == 7846) { ts->msg_count++; m++; spi_message_init(m); m->context = ts; x++; packet->read_z1 = READ_Z1(vref); x->tx_buf = &packet->read_z1; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.z1; x->len = 2; spi_message_add_tail(x, m); /* ... maybe discard first sample ... */ if (pdata->settle_delay_usecs) { x->delay_usecs = pdata->settle_delay_usecs; x++; x->tx_buf = &packet->read_z1; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.z1; x->len = 2; spi_message_add_tail(x, m); } ts->msg_count++; m++; spi_message_init(m); m->context = ts; x++; packet->read_z2 = READ_Z2(vref); x->tx_buf = &packet->read_z2; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.z2; x->len = 2; spi_message_add_tail(x, m); /* ... maybe discard first sample ... */ if (pdata->settle_delay_usecs) { x->delay_usecs = pdata->settle_delay_usecs; x++; x->tx_buf = &packet->read_z2; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->tc.z2; x->len = 2; spi_message_add_tail(x, m); } } /* power down */ ts->msg_count++; m++; spi_message_init(m); m->context = ts; if (ts->model == 7845) { x++; packet->pwrdown_cmd[0] = PWRDOWN; packet->pwrdown_cmd[1] = 0; packet->pwrdown_cmd[2] = 0; x->tx_buf = &packet->pwrdown_cmd[0]; x->len = 3; } else { x++; packet->pwrdown = PWRDOWN; x->tx_buf = &packet->pwrdown; x->len = 1; spi_message_add_tail(x, m); x++; x->rx_buf = &packet->dummy; x->len = 2; } CS_CHANGE(*x); spi_message_add_tail(x, m); } #ifdef CONFIG_OF static const struct of_device_id ads7846_dt_ids[] = { { .compatible = "ti,tsc2046", .data = (void *) 7846 }, { .compatible = "ti,ads7843", .data = (void *) 7843 }, { .compatible = "ti,ads7845", .data = (void *) 7845 }, { .compatible = "ti,ads7846", .data = (void *) 7846 }, { .compatible = "ti,ads7873", .data = (void *) 7873 }, { } }; MODULE_DEVICE_TABLE(of, ads7846_dt_ids); static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) { struct ads7846_platform_data *pdata; struct device_node *node = dev->of_node; const struct of_device_id *match; if (!node) { dev_err(dev, "Device does not have associated DT data\n"); return ERR_PTR(-EINVAL); } match = of_match_device(ads7846_dt_ids, dev); if (!match) { dev_err(dev, "Unknown device model\n"); return ERR_PTR(-EINVAL); } pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return ERR_PTR(-ENOMEM); pdata->model = (unsigned long)match->data; of_property_read_u16(node, "ti,vref-delay-usecs", &pdata->vref_delay_usecs); of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv); pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on"); pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy"); of_property_read_u16(node, "ti,settle-delay-usec", &pdata->settle_delay_usecs); of_property_read_u16(node, "ti,penirq-recheck-delay-usecs", &pdata->penirq_recheck_delay_usecs); of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms); of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms); of_property_read_u16(node, "ti,x-min", &pdata->x_min); of_property_read_u16(node, "ti,y-min", &pdata->y_min); of_property_read_u16(node, "ti,x-max", &pdata->x_max); of_property_read_u16(node, "ti,y-max", &pdata->y_max); of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min); of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max); of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max); of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol); of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep); of_property_read_u32(node, "ti,pendown-gpio-debounce", &pdata->gpio_pendown_debounce); pdata->wakeup = of_property_read_bool(node, "wakeup-source") || of_property_read_bool(node, "linux,wakeup"); pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0); return pdata; } #else static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev) { dev_err(dev, "no platform data defined\n"); return ERR_PTR(-EINVAL); } #endif static int ads7846_probe(struct spi_device *spi) { const struct ads7846_platform_data *pdata; struct ads7846 *ts; struct ads7846_packet *packet; struct input_dev *input_dev; unsigned long irq_flags; int err; if (!spi->irq) { dev_dbg(&spi->dev, "no IRQ?\n"); return -EINVAL; } /* don't exceed max specified sample rate */ if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { dev_err(&spi->dev, "f(sample) %d KHz?\n", (spi->max_speed_hz/SAMPLE_BITS)/1000); return -EINVAL; } /* * We'd set TX word size 8 bits and RX word size to 13 bits ... except * that even if the hardware can do that, the SPI controller driver * may not. So we stick to very-portable 8 bit words, both RX and TX. */ spi->bits_per_word = 8; spi->mode = SPI_MODE_0; err = spi_setup(spi); if (err < 0) return err; ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); input_dev = input_allocate_device(); if (!ts || !packet || !input_dev) { err = -ENOMEM; goto err_free_mem; } spi_set_drvdata(spi, ts); ts->packet = packet; ts->spi = spi; ts->input = input_dev; mutex_init(&ts->lock); init_waitqueue_head(&ts->wait); pdata = dev_get_platdata(&spi->dev); if (!pdata) { pdata = ads7846_probe_dt(&spi->dev); if (IS_ERR(pdata)) { err = PTR_ERR(pdata); goto err_free_mem; } } ts->model = pdata->model ? : 7846; ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; ts->pressure_max = pdata->pressure_max ? : ~0; ts->vref_mv = pdata->vref_mv; ts->swap_xy = pdata->swap_xy; if (pdata->filter != NULL) { if (pdata->filter_init != NULL) { err = pdata->filter_init(pdata, &ts->filter_data); if (err < 0) goto err_free_mem; } ts->filter = pdata->filter; ts->filter_cleanup = pdata->filter_cleanup; } else if (pdata->debounce_max) { ts->debounce_max = pdata->debounce_max; if (ts->debounce_max < 2) ts->debounce_max = 2; ts->debounce_tol = pdata->debounce_tol; ts->debounce_rep = pdata->debounce_rep; ts->filter = ads7846_debounce_filter; ts->filter_data = ts; } else { ts->filter = ads7846_no_filter; } err = ads7846_setup_pendown(spi, ts, pdata); if (err) goto err_cleanup_filter; if (pdata->penirq_recheck_delay_usecs) ts->penirq_recheck_delay_usecs = pdata->penirq_recheck_delay_usecs; ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); input_dev->name = ts->name; input_dev->phys = ts->phys; input_dev->dev.parent = &spi->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, pdata->x_min ? : 0, pdata->x_max ? : MAX_12BIT, 0, 0); input_set_abs_params(input_dev, ABS_Y, pdata->y_min ? : 0, pdata->y_max ? : MAX_12BIT, 0, 0); input_set_abs_params(input_dev, ABS_PRESSURE, pdata->pressure_min, pdata->pressure_max, 0, 0); ads7846_setup_spi_msg(ts, pdata); ts->reg = regulator_get(&spi->dev, "vcc"); if (IS_ERR(ts->reg)) { err = PTR_ERR(ts->reg); dev_err(&spi->dev, "unable to get regulator: %d\n", err); goto err_free_gpio; } err = regulator_enable(ts->reg); if (err) { dev_err(&spi->dev, "unable to enable regulator: %d\n", err); goto err_put_regulator; } irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; irq_flags |= IRQF_ONESHOT; err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, irq_flags, spi->dev.driver->name, ts); if (err && !pdata->irq_flags) { dev_info(&spi->dev, "trying pin change workaround on irq %d\n", spi->irq); irq_flags |= IRQF_TRIGGER_RISING; err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, irq_flags, spi->dev.driver->name, ts); } if (err) { dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); goto err_disable_regulator; } err = ads784x_hwmon_register(spi, ts); if (err) goto err_free_irq; dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); /* * Take a first sample, leaving nPENIRQ active and vREF off; avoid * the touchscreen, in case it's not connected. */ if (ts->model == 7845) ads7845_read12_ser(&spi->dev, PWRDOWN); else (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux)); err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); if (err) goto err_remove_hwmon; err = input_register_device(input_dev); if (err) goto err_remove_attr_group; device_init_wakeup(&spi->dev, pdata->wakeup); /* * If device does not carry platform data we must have allocated it * when parsing DT data. */ if (!dev_get_platdata(&spi->dev)) devm_kfree(&spi->dev, (void *)pdata); return 0; err_remove_attr_group: sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); err_remove_hwmon: ads784x_hwmon_unregister(spi, ts); err_free_irq: free_irq(spi->irq, ts); err_disable_regulator: regulator_disable(ts->reg); err_put_regulator: regulator_put(ts->reg); err_free_gpio: if (!ts->get_pendown_state) gpio_free(ts->gpio_pendown); err_cleanup_filter: if (ts->filter_cleanup) ts->filter_cleanup(ts->filter_data); err_free_mem: input_free_device(input_dev); kfree(packet); kfree(ts); return err; } static int ads7846_remove(struct spi_device *spi) { struct ads7846 *ts = spi_get_drvdata(spi); sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); ads7846_disable(ts); free_irq(ts->spi->irq, ts); input_unregister_device(ts->input); ads784x_hwmon_unregister(spi, ts); regulator_put(ts->reg); if (!ts->get_pendown_state) { /* * If we are not using specialized pendown method we must * have been relying on gpio we set up ourselves. */ gpio_free(ts->gpio_pendown); } if (ts->filter_cleanup) ts->filter_cleanup(ts->filter_data); kfree(ts->packet); kfree(ts); dev_dbg(&spi->dev, "unregistered touchscreen\n"); return 0; } static struct spi_driver ads7846_driver = { .driver = { .name = "ads7846", .pm = &ads7846_pm, .of_match_table = of_match_ptr(ads7846_dt_ids), }, .probe = ads7846_probe, .remove = ads7846_remove, }; module_spi_driver(ads7846_driver); MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("spi:ads7846");
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