From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- drivers/input/touchscreen/wm9705.c | 346 +++++++++++++++++++++++++++++++++++++ 1 file changed, 346 insertions(+) create mode 100644 drivers/input/touchscreen/wm9705.c (limited to 'drivers/input/touchscreen/wm9705.c') diff --git a/drivers/input/touchscreen/wm9705.c b/drivers/input/touchscreen/wm9705.c new file mode 100644 index 000000000..96484aae0 --- /dev/null +++ b/drivers/input/touchscreen/wm9705.c @@ -0,0 +1,346 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * wm9705.c -- Codec driver for Wolfson WM9705 AC97 Codec. + * + * Copyright 2003, 2004, 2005, 2006, 2007 Wolfson Microelectronics PLC. + * Author: Liam Girdwood + * Parts Copyright : Ian Molton + * Andrew Zabolotny + * Russell King + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define TS_NAME "wm97xx" +#define WM9705_VERSION "1.00" +#define DEFAULT_PRESSURE 0xb0c0 + +/* + * Module parameters + */ + +/* + * Set current used for pressure measurement. + * + * Set pil = 2 to use 400uA + * pil = 1 to use 200uA and + * pil = 0 to disable pressure measurement. + * + * This is used to increase the range of values returned by the adc + * when measureing touchpanel pressure. + */ +static int pil; +module_param(pil, int, 0); +MODULE_PARM_DESC(pil, "Set current used for pressure measurement."); + +/* + * Set threshold for pressure measurement. + * + * Pen down pressure below threshold is ignored. + */ +static int pressure = DEFAULT_PRESSURE & 0xfff; +module_param(pressure, int, 0); +MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement."); + +/* + * Set adc sample delay. + * + * For accurate touchpanel measurements, some settling time may be + * required between the switch matrix applying a voltage across the + * touchpanel plate and the ADC sampling the signal. + * + * This delay can be set by setting delay = n, where n is the array + * position of the delay in the array delay_table below. + * Long delays > 1ms are supported for completeness, but are not + * recommended. + */ +static int delay = 4; +module_param(delay, int, 0); +MODULE_PARM_DESC(delay, "Set adc sample delay."); + +/* + * Pen detect comparator threshold. + * + * 0 to Vmid in 15 steps, 0 = use zero power comparator with Vmid threshold + * i.e. 1 = Vmid/15 threshold + * 15 = Vmid/1 threshold + * + * Adjust this value if you are having problems with pen detect not + * detecting any down events. + */ +static int pdd = 8; +module_param(pdd, int, 0); +MODULE_PARM_DESC(pdd, "Set pen detect comparator threshold"); + +/* + * Set adc mask function. + * + * Sources of glitch noise, such as signals driving an LCD display, may feed + * through to the touch screen plates and affect measurement accuracy. In + * order to minimise this, a signal may be applied to the MASK pin to delay or + * synchronise the sampling. + * + * 0 = No delay or sync + * 1 = High on pin stops conversions + * 2 = Edge triggered, edge on pin delays conversion by delay param (above) + * 3 = Edge triggered, edge on pin starts conversion after delay param + */ +static int mask; +module_param(mask, int, 0); +MODULE_PARM_DESC(mask, "Set adc mask function."); + +/* + * ADC sample delay times in uS + */ +static const int delay_table[] = { + 21, /* 1 AC97 Link frames */ + 42, /* 2 */ + 84, /* 4 */ + 167, /* 8 */ + 333, /* 16 */ + 667, /* 32 */ + 1000, /* 48 */ + 1333, /* 64 */ + 2000, /* 96 */ + 2667, /* 128 */ + 3333, /* 160 */ + 4000, /* 192 */ + 4667, /* 224 */ + 5333, /* 256 */ + 6000, /* 288 */ + 0 /* No delay, switch matrix always on */ +}; + +/* + * Delay after issuing a POLL command. + * + * The delay is 3 AC97 link frames + the touchpanel settling delay + */ +static inline void poll_delay(int d) +{ + udelay(3 * AC97_LINK_FRAME + delay_table[d]); +} + +/* + * set up the physical settings of the WM9705 + */ +static void wm9705_phy_init(struct wm97xx *wm) +{ + u16 dig1 = 0, dig2 = WM97XX_RPR; + + /* + * mute VIDEO and AUX as they share X and Y touchscreen + * inputs on the WM9705 + */ + wm97xx_reg_write(wm, AC97_AUX, 0x8000); + wm97xx_reg_write(wm, AC97_VIDEO, 0x8000); + + /* touchpanel pressure current*/ + if (pil == 2) { + dig2 |= WM9705_PIL; + dev_dbg(wm->dev, + "setting pressure measurement current to 400uA."); + } else if (pil) + dev_dbg(wm->dev, + "setting pressure measurement current to 200uA."); + if (!pil) + pressure = 0; + + /* polling mode sample settling delay */ + if (delay != 4) { + if (delay < 0 || delay > 15) { + dev_dbg(wm->dev, "supplied delay out of range."); + delay = 4; + } + } + dig1 &= 0xff0f; + dig1 |= WM97XX_DELAY(delay); + dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.", + delay_table[delay]); + + /* WM9705 pdd */ + dig2 |= (pdd & 0x000f); + dev_dbg(wm->dev, "setting pdd to Vmid/%d", 1 - (pdd & 0x000f)); + + /* mask */ + dig2 |= ((mask & 0x3) << 4); + + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2); +} + +static void wm9705_dig_enable(struct wm97xx *wm, int enable) +{ + if (enable) { + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, + wm->dig[2] | WM97XX_PRP_DET_DIG); + wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */ + } else + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, + wm->dig[2] & ~WM97XX_PRP_DET_DIG); +} + +static void wm9705_aux_prepare(struct wm97xx *wm) +{ + memcpy(wm->dig_save, wm->dig, sizeof(wm->dig)); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG); +} + +static void wm9705_dig_restore(struct wm97xx *wm) +{ + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]); +} + +static inline int is_pden(struct wm97xx *wm) +{ + return wm->dig[2] & WM9705_PDEN; +} + +/* + * Read a sample from the WM9705 adc in polling mode. + */ +static int wm9705_poll_sample(struct wm97xx *wm, int adcsel, int *sample) +{ + int timeout = 5 * delay; + bool wants_pen = adcsel & WM97XX_PEN_DOWN; + + if (wants_pen && !wm->pen_probably_down) { + u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); + if (!(data & WM97XX_PEN_DOWN)) + return RC_PENUP; + wm->pen_probably_down = 1; + } + + /* set up digitiser */ + if (wm->mach_ops && wm->mach_ops->pre_sample) + wm->mach_ops->pre_sample(adcsel); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, (adcsel & WM97XX_ADCSEL_MASK) + | WM97XX_POLL | WM97XX_DELAY(delay)); + + /* wait 3 AC97 time slots + delay for conversion */ + poll_delay(delay); + + /* wait for POLL to go low */ + while ((wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER1) & WM97XX_POLL) + && timeout) { + udelay(AC97_LINK_FRAME); + timeout--; + } + + if (timeout == 0) { + /* If PDEN is set, we can get a timeout when pen goes up */ + if (is_pden(wm)) + wm->pen_probably_down = 0; + else + dev_dbg(wm->dev, "adc sample timeout"); + return RC_PENUP; + } + + *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); + if (wm->mach_ops && wm->mach_ops->post_sample) + wm->mach_ops->post_sample(adcsel); + + /* check we have correct sample */ + if ((*sample ^ adcsel) & WM97XX_ADCSEL_MASK) { + dev_dbg(wm->dev, "adc wrong sample, wanted %x got %x", + adcsel & WM97XX_ADCSEL_MASK, + *sample & WM97XX_ADCSEL_MASK); + return RC_PENUP; + } + + if (wants_pen && !(*sample & WM97XX_PEN_DOWN)) { + wm->pen_probably_down = 0; + return RC_PENUP; + } + + return RC_VALID; +} + +/* + * Sample the WM9705 touchscreen in polling mode + */ +static int wm9705_poll_touch(struct wm97xx *wm, struct wm97xx_data *data) +{ + int rc; + + rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_X | WM97XX_PEN_DOWN, &data->x); + if (rc != RC_VALID) + return rc; + rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_Y | WM97XX_PEN_DOWN, &data->y); + if (rc != RC_VALID) + return rc; + if (pil) { + rc = wm9705_poll_sample(wm, WM97XX_ADCSEL_PRES | WM97XX_PEN_DOWN, &data->p); + if (rc != RC_VALID) + return rc; + } else + data->p = DEFAULT_PRESSURE; + + return RC_VALID; +} + +/* + * Enable WM9705 continuous mode, i.e. touch data is streamed across + * an AC97 slot + */ +static int wm9705_acc_enable(struct wm97xx *wm, int enable) +{ + u16 dig1, dig2; + int ret = 0; + + dig1 = wm->dig[1]; + dig2 = wm->dig[2]; + + if (enable) { + /* continuous mode */ + if (wm->mach_ops->acc_startup && + (ret = wm->mach_ops->acc_startup(wm)) < 0) + return ret; + dig1 &= ~(WM97XX_CM_RATE_MASK | WM97XX_ADCSEL_MASK | + WM97XX_DELAY_MASK | WM97XX_SLT_MASK); + dig1 |= WM97XX_CTC | WM97XX_COO | WM97XX_SLEN | + WM97XX_DELAY(delay) | + WM97XX_SLT(wm->acc_slot) | + WM97XX_RATE(wm->acc_rate); + if (pil) + dig1 |= WM97XX_ADCSEL_PRES; + dig2 |= WM9705_PDEN; + } else { + dig1 &= ~(WM97XX_CTC | WM97XX_COO | WM97XX_SLEN); + dig2 &= ~WM9705_PDEN; + if (wm->mach_ops->acc_shutdown) + wm->mach_ops->acc_shutdown(wm); + } + + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1); + wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2); + + return ret; +} + +struct wm97xx_codec_drv wm9705_codec = { + .id = WM9705_ID2, + .name = "wm9705", + .poll_sample = wm9705_poll_sample, + .poll_touch = wm9705_poll_touch, + .acc_enable = wm9705_acc_enable, + .phy_init = wm9705_phy_init, + .dig_enable = wm9705_dig_enable, + .dig_restore = wm9705_dig_restore, + .aux_prepare = wm9705_aux_prepare, +}; +EXPORT_SYMBOL_GPL(wm9705_codec); + +/* Module information */ +MODULE_AUTHOR("Liam Girdwood "); +MODULE_DESCRIPTION("WM9705 Touch Screen Driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1