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9084533e79
This improves accuracy of the touchscreen and hwmon sensor readings, addressing an issue noted by Imre Deak: there's an extra bit written before the sample (12 bits) gets written out. It also catches up to various comments, and makes the /proc/interrupts entry sensible again. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Imre Deak <imre.deak@nokia.com> Cc: Jean Delvare <khali@linux-fr.org> Cc: Dmitry Torokhov <dtor_core@ameritech.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
918 lines
23 KiB
C
918 lines
23 KiB
C
/*
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* ADS7846 based touchscreen and sensor driver
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*
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* Copyright (c) 2005 David Brownell
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* Copyright (c) 2006 Nokia Corporation
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* Various changes: Imre Deak <imre.deak@nokia.com>
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*
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* Using code from:
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* - corgi_ts.c
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* Copyright (C) 2004-2005 Richard Purdie
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* - omap_ts.[hc], ads7846.h, ts_osk.c
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* Copyright (C) 2002 MontaVista Software
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* Copyright (C) 2004 Texas Instruments
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* Copyright (C) 2005 Dirk Behme
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/device.h>
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#include <linux/init.h>
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#include <linux/delay.h>
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#include <linux/input.h>
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#include <linux/interrupt.h>
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#include <linux/slab.h>
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#include <linux/spi/spi.h>
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#include <linux/spi/ads7846.h>
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#include <asm/irq.h>
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#ifdef CONFIG_ARM
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#include <asm/mach-types.h>
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#ifdef CONFIG_ARCH_OMAP
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#include <asm/arch/gpio.h>
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#endif
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#endif
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/*
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* This code has been heavily tested on a Nokia 770, and lightly
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* tested on other ads7846 devices (OSK/Mistral, Lubbock).
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* Support for ads7843 and ads7845 has only been stubbed in.
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*
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* IRQ handling needs a workaround because of a shortcoming in handling
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* edge triggered IRQs on some platforms like the OMAP1/2. These
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* platforms don't handle the ARM lazy IRQ disabling properly, thus we
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* have to maintain our own SW IRQ disabled status. This should be
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* removed as soon as the affected platform's IRQ handling is fixed.
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*
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* app note sbaa036 talks in more detail about accurate sampling...
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* that ought to help in situations like LCDs inducing noise (which
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* can also be helped by using synch signals) and more generally.
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* This driver tries to utilize the measures described in the app
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* note. The strength of filtering can be set in the board-* specific
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* files.
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*/
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#define TS_POLL_PERIOD msecs_to_jiffies(10)
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/* this driver doesn't aim at the peak continuous sample rate */
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#define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
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struct ts_event {
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/* For portability, we can't read 12 bit values using SPI (which
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* would make the controller deliver them as native byteorder u16
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* with msbs zeroed). Instead, we read them as two 8-bit values,
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* which need byteswapping then range adjustment.
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*/
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__be16 x;
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__be16 y;
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__be16 z1, z2;
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int ignore;
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};
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struct ads7846 {
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struct input_dev *input;
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char phys[32];
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struct spi_device *spi;
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u16 model;
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u16 vref_delay_usecs;
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u16 x_plate_ohms;
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u16 pressure_max;
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u8 read_x, read_y, read_z1, read_z2, pwrdown;
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u16 dummy; /* for the pwrdown read */
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struct ts_event tc;
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struct spi_transfer xfer[10];
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struct spi_message msg[5];
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struct spi_message *last_msg;
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int msg_idx;
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int read_cnt;
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int read_rep;
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int last_read;
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u16 debounce_max;
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u16 debounce_tol;
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u16 debounce_rep;
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spinlock_t lock;
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struct timer_list timer; /* P: lock */
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unsigned pendown:1; /* P: lock */
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unsigned pending:1; /* P: lock */
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// FIXME remove "irq_disabled"
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unsigned irq_disabled:1; /* P: lock */
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unsigned disabled:1;
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int (*get_pendown_state)(void);
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};
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/* leave chip selected when we're done, for quicker re-select? */
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#if 0
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#define CS_CHANGE(xfer) ((xfer).cs_change = 1)
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#else
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#define CS_CHANGE(xfer) ((xfer).cs_change = 0)
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#endif
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/*--------------------------------------------------------------------------*/
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/* The ADS7846 has touchscreen and other sensors.
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* Earlier ads784x chips are somewhat compatible.
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*/
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#define ADS_START (1 << 7)
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#define ADS_A2A1A0_d_y (1 << 4) /* differential */
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#define ADS_A2A1A0_d_z1 (3 << 4) /* differential */
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#define ADS_A2A1A0_d_z2 (4 << 4) /* differential */
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#define ADS_A2A1A0_d_x (5 << 4) /* differential */
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#define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */
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#define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */
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#define ADS_A2A1A0_vaux (6 << 4) /* non-differential */
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#define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */
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#define ADS_8_BIT (1 << 3)
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#define ADS_12_BIT (0 << 3)
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#define ADS_SER (1 << 2) /* non-differential */
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#define ADS_DFR (0 << 2) /* differential */
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#define ADS_PD10_PDOWN (0 << 0) /* lowpower mode + penirq */
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#define ADS_PD10_ADC_ON (1 << 0) /* ADC on */
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#define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */
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#define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */
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#define MAX_12BIT ((1<<12)-1)
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/* leave ADC powered up (disables penirq) between differential samples */
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#define READ_12BIT_DFR(x) (ADS_START | ADS_A2A1A0_d_ ## x \
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| ADS_12_BIT | ADS_DFR)
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#define READ_Y (READ_12BIT_DFR(y) | ADS_PD10_ADC_ON)
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#define READ_Z1 (READ_12BIT_DFR(z1) | ADS_PD10_ADC_ON)
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#define READ_Z2 (READ_12BIT_DFR(z2) | ADS_PD10_ADC_ON)
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#define READ_X (READ_12BIT_DFR(x) | ADS_PD10_ADC_ON)
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#define PWRDOWN (READ_12BIT_DFR(y) | ADS_PD10_PDOWN) /* LAST */
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/* single-ended samples need to first power up reference voltage;
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* we leave both ADC and VREF powered
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*/
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#define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \
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| ADS_12_BIT | ADS_SER)
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#define REF_ON (READ_12BIT_DFR(x) | ADS_PD10_ALL_ON)
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#define REF_OFF (READ_12BIT_DFR(y) | ADS_PD10_PDOWN)
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/*--------------------------------------------------------------------------*/
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/*
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* Non-touchscreen sensors only use single-ended conversions.
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*/
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struct ser_req {
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u8 ref_on;
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u8 command;
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u8 ref_off;
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u16 scratch;
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__be16 sample;
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struct spi_message msg;
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struct spi_transfer xfer[6];
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};
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static void ads7846_enable(struct ads7846 *ts);
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static void ads7846_disable(struct ads7846 *ts);
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static int device_suspended(struct device *dev)
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{
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struct ads7846 *ts = dev_get_drvdata(dev);
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return dev->power.power_state.event != PM_EVENT_ON || ts->disabled;
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}
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static int ads7846_read12_ser(struct device *dev, unsigned command)
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{
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struct spi_device *spi = to_spi_device(dev);
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struct ads7846 *ts = dev_get_drvdata(dev);
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struct ser_req *req = kzalloc(sizeof *req, SLAB_KERNEL);
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int status;
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int sample;
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int i;
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if (!req)
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return -ENOMEM;
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spi_message_init(&req->msg);
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/* activate reference, so it has time to settle; */
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req->ref_on = REF_ON;
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req->xfer[0].tx_buf = &req->ref_on;
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req->xfer[0].len = 1;
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req->xfer[1].rx_buf = &req->scratch;
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req->xfer[1].len = 2;
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/*
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* for external VREF, 0 usec (and assume it's always on);
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* for 1uF, use 800 usec;
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* no cap, 100 usec.
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*/
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req->xfer[1].delay_usecs = ts->vref_delay_usecs;
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/* take sample */
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req->command = (u8) command;
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req->xfer[2].tx_buf = &req->command;
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req->xfer[2].len = 1;
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req->xfer[3].rx_buf = &req->sample;
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req->xfer[3].len = 2;
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/* REVISIT: take a few more samples, and compare ... */
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/* turn off reference */
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req->ref_off = REF_OFF;
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req->xfer[4].tx_buf = &req->ref_off;
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req->xfer[4].len = 1;
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req->xfer[5].rx_buf = &req->scratch;
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req->xfer[5].len = 2;
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CS_CHANGE(req->xfer[5]);
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/* group all the transfers together, so we can't interfere with
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* reading touchscreen state; disable penirq while sampling
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*/
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for (i = 0; i < 6; i++)
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spi_message_add_tail(&req->xfer[i], &req->msg);
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ts->irq_disabled = 1;
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disable_irq(spi->irq);
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status = spi_sync(spi, &req->msg);
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ts->irq_disabled = 0;
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enable_irq(spi->irq);
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if (req->msg.status)
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status = req->msg.status;
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/* on-wire is a must-ignore bit, a BE12 value, then padding */
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sample = be16_to_cpu(req->sample);
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sample = sample >> 3;
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sample &= 0x0fff;
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kfree(req);
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return status ? status : sample;
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}
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#define SHOW(name) static ssize_t \
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name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
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{ \
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ssize_t v = ads7846_read12_ser(dev, \
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READ_12BIT_SER(name) | ADS_PD10_ALL_ON); \
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if (v < 0) \
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return v; \
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return sprintf(buf, "%u\n", (unsigned) v); \
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} \
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static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
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SHOW(temp0)
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SHOW(temp1)
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SHOW(vaux)
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SHOW(vbatt)
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static int is_pen_down(struct device *dev)
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{
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struct ads7846 *ts = dev_get_drvdata(dev);
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return ts->pendown;
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}
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static ssize_t ads7846_pen_down_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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return sprintf(buf, "%u\n", is_pen_down(dev));
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}
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static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL);
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static ssize_t ads7846_disable_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct ads7846 *ts = dev_get_drvdata(dev);
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return sprintf(buf, "%u\n", ts->disabled);
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}
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static ssize_t ads7846_disable_store(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t count)
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{
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struct ads7846 *ts = dev_get_drvdata(dev);
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char *endp;
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int i;
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i = simple_strtoul(buf, &endp, 10);
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spin_lock_irq(&ts->lock);
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if (i)
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ads7846_disable(ts);
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else
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ads7846_enable(ts);
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spin_unlock_irq(&ts->lock);
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return count;
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}
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static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store);
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/*--------------------------------------------------------------------------*/
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/*
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* PENIRQ only kicks the timer. The timer only reissues the SPI transfer,
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* to retrieve touchscreen status.
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*
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* The SPI transfer completion callback does the real work. It reports
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* touchscreen events and reactivates the timer (or IRQ) as appropriate.
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*/
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static void ads7846_rx(void *ads)
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{
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struct ads7846 *ts = ads;
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struct input_dev *input_dev = ts->input;
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unsigned Rt;
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unsigned sync = 0;
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u16 x, y, z1, z2;
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unsigned long flags;
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/* adjust: on-wire is a must-ignore bit, a BE12 value, then padding;
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* built from two 8 bit values written msb-first.
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*/
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x = (be16_to_cpu(ts->tc.x) >> 3) & 0x0fff;
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y = (be16_to_cpu(ts->tc.y) >> 3) & 0x0fff;
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z1 = (be16_to_cpu(ts->tc.z1) >> 3) & 0x0fff;
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z2 = (be16_to_cpu(ts->tc.z2) >> 3) & 0x0fff;
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/* range filtering */
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if (x == MAX_12BIT)
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x = 0;
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if (likely(x && z1 && !device_suspended(&ts->spi->dev))) {
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/* compute touch pressure resistance using equation #2 */
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Rt = z2;
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Rt -= z1;
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Rt *= x;
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Rt *= ts->x_plate_ohms;
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Rt /= z1;
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Rt = (Rt + 2047) >> 12;
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} else
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Rt = 0;
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/* Sample found inconsistent by debouncing or pressure is beyond
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* the maximum. Don't report it to user space, repeat at least
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* once more the measurement */
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if (ts->tc.ignore || Rt > ts->pressure_max) {
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mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
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return;
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}
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/* NOTE: "pendown" is inferred from pressure; we don't rely on
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* being able to check nPENIRQ status, or "friendly" trigger modes
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* (both-edges is much better than just-falling or low-level).
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*
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* REVISIT: some boards may require reading nPENIRQ; it's
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* needed on 7843. and 7845 reads pressure differently...
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*
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* REVISIT: the touchscreen might not be connected; this code
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* won't notice that, even if nPENIRQ never fires ...
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*/
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if (!ts->pendown && Rt != 0) {
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input_report_key(input_dev, BTN_TOUCH, 1);
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sync = 1;
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} else if (ts->pendown && Rt == 0) {
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input_report_key(input_dev, BTN_TOUCH, 0);
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sync = 1;
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}
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if (Rt) {
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input_report_abs(input_dev, ABS_X, x);
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input_report_abs(input_dev, ABS_Y, y);
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sync = 1;
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}
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if (sync) {
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input_report_abs(input_dev, ABS_PRESSURE, Rt);
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input_sync(input_dev);
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}
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#ifdef VERBOSE
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if (Rt || ts->pendown)
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pr_debug("%s: %d/%d/%d%s\n", ts->spi->dev.bus_id,
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x, y, Rt, Rt ? "" : " UP");
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#endif
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spin_lock_irqsave(&ts->lock, flags);
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ts->pendown = (Rt != 0);
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mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD);
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spin_unlock_irqrestore(&ts->lock, flags);
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}
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static void ads7846_debounce(void *ads)
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{
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struct ads7846 *ts = ads;
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struct spi_message *m;
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struct spi_transfer *t;
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int val;
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int status;
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m = &ts->msg[ts->msg_idx];
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t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
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val = (be16_to_cpu(*(__be16 *)t->rx_buf) >> 3) & 0x0fff;
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if (!ts->read_cnt || (abs(ts->last_read - val) > ts->debounce_tol)) {
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/* Repeat it, if this was the first read or the read
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* wasn't consistent enough. */
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if (ts->read_cnt < ts->debounce_max) {
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ts->last_read = val;
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ts->read_cnt++;
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} else {
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/* Maximum number of debouncing reached and still
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* not enough number of consistent readings. Abort
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* the whole sample, repeat it in the next sampling
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* period.
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*/
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ts->tc.ignore = 1;
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ts->read_cnt = 0;
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/* Last message will contain ads7846_rx() as the
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* completion function.
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*/
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m = ts->last_msg;
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}
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/* Start over collecting consistent readings. */
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ts->read_rep = 0;
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} else {
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if (++ts->read_rep > ts->debounce_rep) {
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/* Got a good reading for this coordinate,
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* go for the next one. */
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ts->tc.ignore = 0;
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ts->msg_idx++;
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ts->read_cnt = 0;
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ts->read_rep = 0;
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m++;
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} else
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/* Read more values that are consistent. */
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ts->read_cnt++;
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}
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status = spi_async(ts->spi, m);
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if (status)
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dev_err(&ts->spi->dev, "spi_async --> %d\n",
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status);
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}
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static void ads7846_timer(unsigned long handle)
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{
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struct ads7846 *ts = (void *)handle;
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int status = 0;
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spin_lock_irq(&ts->lock);
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if (unlikely(ts->msg_idx && !ts->pendown)) {
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/* measurement cycle ended */
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if (!device_suspended(&ts->spi->dev)) {
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ts->irq_disabled = 0;
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enable_irq(ts->spi->irq);
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}
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ts->pending = 0;
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ts->msg_idx = 0;
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} else {
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/* pen is still down, continue with the measurement */
|
|
ts->msg_idx = 0;
|
|
status = spi_async(ts->spi, &ts->msg[0]);
|
|
if (status)
|
|
dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
|
|
}
|
|
|
|
spin_unlock_irq(&ts->lock);
|
|
}
|
|
|
|
static irqreturn_t ads7846_irq(int irq, void *handle, struct pt_regs *regs)
|
|
{
|
|
struct ads7846 *ts = handle;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&ts->lock, flags);
|
|
if (likely(ts->get_pendown_state())) {
|
|
if (!ts->irq_disabled) {
|
|
/* The ARM do_simple_IRQ() dispatcher doesn't act
|
|
* like the other dispatchers: it will report IRQs
|
|
* even after they've been disabled. We work around
|
|
* that here. (The "generic irq" framework may help...)
|
|
*/
|
|
ts->irq_disabled = 1;
|
|
disable_irq(ts->spi->irq);
|
|
ts->pending = 1;
|
|
mod_timer(&ts->timer, jiffies);
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&ts->lock, flags);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*--------------------------------------------------------------------------*/
|
|
|
|
/* Must be called with ts->lock held */
|
|
static void ads7846_disable(struct ads7846 *ts)
|
|
{
|
|
if (ts->disabled)
|
|
return;
|
|
|
|
ts->disabled = 1;
|
|
|
|
/* are we waiting for IRQ, or polling? */
|
|
if (!ts->pending) {
|
|
ts->irq_disabled = 1;
|
|
disable_irq(ts->spi->irq);
|
|
} else {
|
|
/* the timer will run at least once more, and
|
|
* leave everything in a clean state, IRQ disabled
|
|
*/
|
|
while (ts->pending) {
|
|
spin_unlock_irq(&ts->lock);
|
|
msleep(1);
|
|
spin_lock_irq(&ts->lock);
|
|
}
|
|
}
|
|
|
|
/* we know the chip's in lowpower 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)
|
|
{
|
|
if (!ts->disabled)
|
|
return;
|
|
|
|
ts->disabled = 0;
|
|
ts->irq_disabled = 0;
|
|
enable_irq(ts->spi->irq);
|
|
}
|
|
|
|
static int ads7846_suspend(struct spi_device *spi, pm_message_t message)
|
|
{
|
|
struct ads7846 *ts = dev_get_drvdata(&spi->dev);
|
|
|
|
spin_lock_irq(&ts->lock);
|
|
|
|
spi->dev.power.power_state = message;
|
|
ads7846_disable(ts);
|
|
|
|
spin_unlock_irq(&ts->lock);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
static int ads7846_resume(struct spi_device *spi)
|
|
{
|
|
struct ads7846 *ts = dev_get_drvdata(&spi->dev);
|
|
|
|
spin_lock_irq(&ts->lock);
|
|
|
|
spi->dev.power.power_state = PMSG_ON;
|
|
ads7846_enable(ts);
|
|
|
|
spin_unlock_irq(&ts->lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __devinit ads7846_probe(struct spi_device *spi)
|
|
{
|
|
struct ads7846 *ts;
|
|
struct input_dev *input_dev;
|
|
struct ads7846_platform_data *pdata = spi->dev.platform_data;
|
|
struct spi_message *m;
|
|
struct spi_transfer *x;
|
|
int err;
|
|
|
|
if (!spi->irq) {
|
|
dev_dbg(&spi->dev, "no IRQ?\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (!pdata) {
|
|
dev_dbg(&spi->dev, "no platform data?\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* don't exceed max specified sample rate */
|
|
if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
|
|
dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
|
|
(spi->max_speed_hz/SAMPLE_BITS)/1000);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* 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 == NULL) {
|
|
dev_dbg(&spi->dev, "no get_pendown_state function?\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* We'd set TX wordsize 8 bits and RX wordsize 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;
|
|
|
|
ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
|
|
input_dev = input_allocate_device();
|
|
if (!ts || !input_dev) {
|
|
err = -ENOMEM;
|
|
goto err_free_mem;
|
|
}
|
|
|
|
dev_set_drvdata(&spi->dev, ts);
|
|
spi->dev.power.power_state = PMSG_ON;
|
|
|
|
ts->spi = spi;
|
|
ts->input = input_dev;
|
|
|
|
init_timer(&ts->timer);
|
|
ts->timer.data = (unsigned long) ts;
|
|
ts->timer.function = ads7846_timer;
|
|
|
|
spin_lock_init(&ts->lock);
|
|
|
|
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;
|
|
if (pdata->debounce_max) {
|
|
ts->debounce_max = pdata->debounce_max;
|
|
ts->debounce_tol = pdata->debounce_tol;
|
|
ts->debounce_rep = pdata->debounce_rep;
|
|
if (ts->debounce_rep > ts->debounce_max + 1)
|
|
ts->debounce_rep = ts->debounce_max - 1;
|
|
} else
|
|
ts->debounce_tol = ~0;
|
|
ts->get_pendown_state = pdata->get_pendown_state;
|
|
|
|
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", spi->dev.bus_id);
|
|
|
|
input_dev->name = "ADS784x Touchscreen";
|
|
input_dev->phys = ts->phys;
|
|
input_dev->cdev.dev = &spi->dev;
|
|
|
|
input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
|
|
input_dev->keybit[LONG(BTN_TOUCH)] = BIT(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);
|
|
|
|
/* set up the transfers to read touchscreen state; this assumes we
|
|
* use formula #2 for pressure, not #3.
|
|
*/
|
|
m = &ts->msg[0];
|
|
x = ts->xfer;
|
|
|
|
spi_message_init(m);
|
|
|
|
/* y- still on; turn on only y+ (and ADC) */
|
|
ts->read_y = READ_Y;
|
|
x->tx_buf = &ts->read_y;
|
|
x->len = 1;
|
|
spi_message_add_tail(x, m);
|
|
|
|
x++;
|
|
x->rx_buf = &ts->tc.y;
|
|
x->len = 2;
|
|
spi_message_add_tail(x, m);
|
|
|
|
m->complete = ads7846_debounce;
|
|
m->context = ts;
|
|
|
|
m++;
|
|
spi_message_init(m);
|
|
|
|
/* turn y- off, x+ on, then leave in lowpower */
|
|
x++;
|
|
ts->read_x = READ_X;
|
|
x->tx_buf = &ts->read_x;
|
|
x->len = 1;
|
|
spi_message_add_tail(x, m);
|
|
|
|
x++;
|
|
x->rx_buf = &ts->tc.x;
|
|
x->len = 2;
|
|
spi_message_add_tail(x, m);
|
|
|
|
m->complete = ads7846_debounce;
|
|
m->context = ts;
|
|
|
|
/* turn y+ off, x- on; we'll use formula #2 */
|
|
if (ts->model == 7846) {
|
|
m++;
|
|
spi_message_init(m);
|
|
|
|
x++;
|
|
ts->read_z1 = READ_Z1;
|
|
x->tx_buf = &ts->read_z1;
|
|
x->len = 1;
|
|
spi_message_add_tail(x, m);
|
|
|
|
x++;
|
|
x->rx_buf = &ts->tc.z1;
|
|
x->len = 2;
|
|
spi_message_add_tail(x, m);
|
|
|
|
m->complete = ads7846_debounce;
|
|
m->context = ts;
|
|
|
|
m++;
|
|
spi_message_init(m);
|
|
|
|
x++;
|
|
ts->read_z2 = READ_Z2;
|
|
x->tx_buf = &ts->read_z2;
|
|
x->len = 1;
|
|
spi_message_add_tail(x, m);
|
|
|
|
x++;
|
|
x->rx_buf = &ts->tc.z2;
|
|
x->len = 2;
|
|
spi_message_add_tail(x, m);
|
|
|
|
m->complete = ads7846_debounce;
|
|
m->context = ts;
|
|
}
|
|
|
|
/* power down */
|
|
m++;
|
|
spi_message_init(m);
|
|
|
|
x++;
|
|
ts->pwrdown = PWRDOWN;
|
|
x->tx_buf = &ts->pwrdown;
|
|
x->len = 1;
|
|
spi_message_add_tail(x, m);
|
|
|
|
x++;
|
|
x->rx_buf = &ts->dummy;
|
|
x->len = 2;
|
|
CS_CHANGE(*x);
|
|
spi_message_add_tail(x, m);
|
|
|
|
m->complete = ads7846_rx;
|
|
m->context = ts;
|
|
|
|
ts->last_msg = m;
|
|
|
|
if (request_irq(spi->irq, ads7846_irq,
|
|
SA_SAMPLE_RANDOM | SA_TRIGGER_FALLING,
|
|
spi->dev.driver->name, ts)) {
|
|
dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
|
|
err = -EBUSY;
|
|
goto err_free_mem;
|
|
}
|
|
|
|
dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);
|
|
|
|
/* take a first sample, leaving nPENIRQ active; avoid
|
|
* the touchscreen, in case it's not connected.
|
|
*/
|
|
(void) ads7846_read12_ser(&spi->dev,
|
|
READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON);
|
|
|
|
/* ads7843/7845 don't have temperature sensors, and
|
|
* use the other sensors a bit differently too
|
|
*/
|
|
if (ts->model == 7846) {
|
|
device_create_file(&spi->dev, &dev_attr_temp0);
|
|
device_create_file(&spi->dev, &dev_attr_temp1);
|
|
}
|
|
if (ts->model != 7845)
|
|
device_create_file(&spi->dev, &dev_attr_vbatt);
|
|
device_create_file(&spi->dev, &dev_attr_vaux);
|
|
|
|
device_create_file(&spi->dev, &dev_attr_pen_down);
|
|
|
|
device_create_file(&spi->dev, &dev_attr_disable);
|
|
|
|
err = input_register_device(input_dev);
|
|
if (err)
|
|
goto err_remove_attr;
|
|
|
|
return 0;
|
|
|
|
err_remove_attr:
|
|
device_remove_file(&spi->dev, &dev_attr_disable);
|
|
device_remove_file(&spi->dev, &dev_attr_pen_down);
|
|
if (ts->model == 7846) {
|
|
device_remove_file(&spi->dev, &dev_attr_temp1);
|
|
device_remove_file(&spi->dev, &dev_attr_temp0);
|
|
}
|
|
if (ts->model != 7845)
|
|
device_remove_file(&spi->dev, &dev_attr_vbatt);
|
|
device_remove_file(&spi->dev, &dev_attr_vaux);
|
|
|
|
free_irq(spi->irq, ts);
|
|
err_free_mem:
|
|
input_free_device(input_dev);
|
|
kfree(ts);
|
|
return err;
|
|
}
|
|
|
|
static int __devexit ads7846_remove(struct spi_device *spi)
|
|
{
|
|
struct ads7846 *ts = dev_get_drvdata(&spi->dev);
|
|
|
|
input_unregister_device(ts->input);
|
|
|
|
ads7846_suspend(spi, PMSG_SUSPEND);
|
|
|
|
device_remove_file(&spi->dev, &dev_attr_disable);
|
|
device_remove_file(&spi->dev, &dev_attr_pen_down);
|
|
if (ts->model == 7846) {
|
|
device_remove_file(&spi->dev, &dev_attr_temp1);
|
|
device_remove_file(&spi->dev, &dev_attr_temp0);
|
|
}
|
|
if (ts->model != 7845)
|
|
device_remove_file(&spi->dev, &dev_attr_vbatt);
|
|
device_remove_file(&spi->dev, &dev_attr_vaux);
|
|
|
|
free_irq(ts->spi->irq, ts);
|
|
/* suspend left the IRQ disabled */
|
|
enable_irq(ts->spi->irq);
|
|
|
|
kfree(ts);
|
|
|
|
dev_dbg(&spi->dev, "unregistered touchscreen\n");
|
|
return 0;
|
|
}
|
|
|
|
static struct spi_driver ads7846_driver = {
|
|
.driver = {
|
|
.name = "ads7846",
|
|
.bus = &spi_bus_type,
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = ads7846_probe,
|
|
.remove = __devexit_p(ads7846_remove),
|
|
.suspend = ads7846_suspend,
|
|
.resume = ads7846_resume,
|
|
};
|
|
|
|
static int __init ads7846_init(void)
|
|
{
|
|
/* grr, board-specific init should stay out of drivers!! */
|
|
|
|
#ifdef CONFIG_ARCH_OMAP
|
|
if (machine_is_omap_osk()) {
|
|
/* GPIO4 = PENIRQ; GPIO6 = BUSY */
|
|
omap_request_gpio(4);
|
|
omap_set_gpio_direction(4, 1);
|
|
omap_request_gpio(6);
|
|
omap_set_gpio_direction(6, 1);
|
|
}
|
|
// also TI 1510 Innovator, bitbanging through FPGA
|
|
// also Nokia 770
|
|
// also Palm Tungsten T2
|
|
#endif
|
|
|
|
// PXA:
|
|
// also Dell Axim X50
|
|
// also HP iPaq H191x/H192x/H415x/H435x
|
|
// also Intel Lubbock (additional to UCB1400; as temperature sensor)
|
|
// also Sharp Zaurus C7xx, C8xx (corgi/sheperd/husky)
|
|
|
|
// Atmel at91sam9261-EK uses ads7843
|
|
|
|
// also various AMD Au1x00 devel boards
|
|
|
|
return spi_register_driver(&ads7846_driver);
|
|
}
|
|
module_init(ads7846_init);
|
|
|
|
static void __exit ads7846_exit(void)
|
|
{
|
|
spi_unregister_driver(&ads7846_driver);
|
|
|
|
#ifdef CONFIG_ARCH_OMAP
|
|
if (machine_is_omap_osk()) {
|
|
omap_free_gpio(4);
|
|
omap_free_gpio(6);
|
|
}
|
|
#endif
|
|
|
|
}
|
|
module_exit(ads7846_exit);
|
|
|
|
MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
|
|
MODULE_LICENSE("GPL");
|