// SPDX-License-Identifier: GPL-2.0-only /* * Synaptics NavPoint (PXA27x SSP/SPI) driver. * * Copyright (C) 2012 Paul Parsons <lost.distance@yahoo.com> */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/clk.h> #include <linux/delay.h> #include <linux/gpio.h> #include <linux/input.h> #include <linux/input/navpoint.h> #include <linux/interrupt.h> #include <linux/mutex.h> #include <linux/pxa2xx_ssp.h> #include <linux/slab.h> /* * Synaptics Modular Embedded Protocol: Module Packet Format. * Module header byte 2:0 = Length (# bytes that follow) * Module header byte 4:3 = Control * Module header byte 7:5 = Module Address */ #define HEADER_LENGTH(byte) ((byte) & 0x07) #define HEADER_CONTROL(byte) (((byte) >> 3) & 0x03) #define HEADER_ADDRESS(byte) ((byte) >> 5) struct navpoint { struct ssp_device *ssp; struct input_dev *input; struct device *dev; int gpio; int index; u8 data[1 + HEADER_LENGTH(0xff)]; }; /* * Initialization values for SSCR0_x, SSCR1_x, SSSR_x. */ static const u32 sscr0 = 0 | SSCR0_TUM /* TIM = 1; No TUR interrupts */ | SSCR0_RIM /* RIM = 1; No ROR interrupts */ | SSCR0_SSE /* SSE = 1; SSP enabled */ | SSCR0_Motorola /* FRF = 0; Motorola SPI */ | SSCR0_DataSize(16) /* DSS = 15; Data size = 16-bit */ ; static const u32 sscr1 = 0 | SSCR1_SCFR /* SCFR = 1; SSPSCLK only during transfers */ | SSCR1_SCLKDIR /* SCLKDIR = 1; Slave mode */ | SSCR1_SFRMDIR /* SFRMDIR = 1; Slave mode */ | SSCR1_RWOT /* RWOT = 1; Receive without transmit mode */ | SSCR1_RxTresh(1) /* RFT = 0; Receive FIFO threshold = 1 */ | SSCR1_SPH /* SPH = 1; SSPSCLK inactive 0.5 + 1 cycles */ | SSCR1_RIE /* RIE = 1; Receive FIFO interrupt enabled */ ; static const u32 sssr = 0 | SSSR_BCE /* BCE = 1; Clear BCE */ | SSSR_TUR /* TUR = 1; Clear TUR */ | SSSR_EOC /* EOC = 1; Clear EOC */ | SSSR_TINT /* TINT = 1; Clear TINT */ | SSSR_PINT /* PINT = 1; Clear PINT */ | SSSR_ROR /* ROR = 1; Clear ROR */ ; /* * MEP Query $22: Touchpad Coordinate Range Query is not supported by * the NavPoint module, so sampled values provide the default limits. */ #define NAVPOINT_X_MIN 1278 #define NAVPOINT_X_MAX 5340 #define NAVPOINT_Y_MIN 1572 #define NAVPOINT_Y_MAX 4396 #define NAVPOINT_PRESSURE_MIN 0 #define NAVPOINT_PRESSURE_MAX 255 static void navpoint_packet(struct navpoint *navpoint) { int finger; int gesture; int x, y, z; switch (navpoint->data[0]) { case 0xff: /* Garbage (packet?) between reset and Hello packet */ case 0x00: /* Module 0, NULL packet */ break; case 0x0e: /* Module 0, Absolute packet */ finger = (navpoint->data[1] & 0x01); gesture = (navpoint->data[1] & 0x02); x = ((navpoint->data[2] & 0x1f) << 8) | navpoint->data[3]; y = ((navpoint->data[4] & 0x1f) << 8) | navpoint->data[5]; z = navpoint->data[6]; input_report_key(navpoint->input, BTN_TOUCH, finger); input_report_abs(navpoint->input, ABS_X, x); input_report_abs(navpoint->input, ABS_Y, y); input_report_abs(navpoint->input, ABS_PRESSURE, z); input_report_key(navpoint->input, BTN_TOOL_FINGER, finger); input_report_key(navpoint->input, BTN_LEFT, gesture); input_sync(navpoint->input); break; case 0x19: /* Module 0, Hello packet */ if ((navpoint->data[1] & 0xf0) == 0x10) break; fallthrough; default: dev_warn(navpoint->dev, "spurious packet: data=0x%02x,0x%02x,...\n", navpoint->data[0], navpoint->data[1]); break; } } static irqreturn_t navpoint_irq(int irq, void *dev_id) { struct navpoint *navpoint = dev_id; struct ssp_device *ssp = navpoint->ssp; irqreturn_t ret = IRQ_NONE; u32 status; status = pxa_ssp_read_reg(ssp, SSSR); if (status & sssr) { dev_warn(navpoint->dev, "unexpected interrupt: status=0x%08x\n", status); pxa_ssp_write_reg(ssp, SSSR, (status & sssr)); ret = IRQ_HANDLED; } while (status & SSSR_RNE) { u32 data; data = pxa_ssp_read_reg(ssp, SSDR); navpoint->data[navpoint->index + 0] = (data >> 8); navpoint->data[navpoint->index + 1] = data; navpoint->index += 2; if (HEADER_LENGTH(navpoint->data[0]) < navpoint->index) { navpoint_packet(navpoint); navpoint->index = 0; } status = pxa_ssp_read_reg(ssp, SSSR); ret = IRQ_HANDLED; } return ret; } static void navpoint_up(struct navpoint *navpoint) { struct ssp_device *ssp = navpoint->ssp; int timeout; clk_prepare_enable(ssp->clk); pxa_ssp_write_reg(ssp, SSCR1, sscr1); pxa_ssp_write_reg(ssp, SSSR, sssr); pxa_ssp_write_reg(ssp, SSTO, 0); pxa_ssp_write_reg(ssp, SSCR0, sscr0); /* SSCR0_SSE written last */ /* Wait until SSP port is ready for slave clock operations */ for (timeout = 100; timeout != 0; --timeout) { if (!(pxa_ssp_read_reg(ssp, SSSR) & SSSR_CSS)) break; msleep(1); } if (timeout == 0) dev_err(navpoint->dev, "timeout waiting for SSSR[CSS] to clear\n"); if (gpio_is_valid(navpoint->gpio)) gpio_set_value(navpoint->gpio, 1); } static void navpoint_down(struct navpoint *navpoint) { struct ssp_device *ssp = navpoint->ssp; if (gpio_is_valid(navpoint->gpio)) gpio_set_value(navpoint->gpio, 0); pxa_ssp_write_reg(ssp, SSCR0, 0); clk_disable_unprepare(ssp->clk); } static int navpoint_open(struct input_dev *input) { struct navpoint *navpoint = input_get_drvdata(input); navpoint_up(navpoint); return 0; } static void navpoint_close(struct input_dev *input) { struct navpoint *navpoint = input_get_drvdata(input); navpoint_down(navpoint); } static int navpoint_probe(struct platform_device *pdev) { const struct navpoint_platform_data *pdata = dev_get_platdata(&pdev->dev); struct ssp_device *ssp; struct input_dev *input; struct navpoint *navpoint; int error; if (!pdata) { dev_err(&pdev->dev, "no platform data\n"); return -EINVAL; } if (gpio_is_valid(pdata->gpio)) { error = gpio_request_one(pdata->gpio, GPIOF_OUT_INIT_LOW, "SYNAPTICS_ON"); if (error) return error; } ssp = pxa_ssp_request(pdata->port, pdev->name); if (!ssp) { error = -ENODEV; goto err_free_gpio; } /* HaRET does not disable devices before jumping into Linux */ if (pxa_ssp_read_reg(ssp, SSCR0) & SSCR0_SSE) { pxa_ssp_write_reg(ssp, SSCR0, 0); dev_warn(&pdev->dev, "ssp%d already enabled\n", pdata->port); } navpoint = kzalloc(sizeof(*navpoint), GFP_KERNEL); input = input_allocate_device(); if (!navpoint || !input) { error = -ENOMEM; goto err_free_mem; } navpoint->ssp = ssp; navpoint->input = input; navpoint->dev = &pdev->dev; navpoint->gpio = pdata->gpio; input->name = pdev->name; input->dev.parent = &pdev->dev; __set_bit(EV_KEY, input->evbit); __set_bit(EV_ABS, input->evbit); __set_bit(BTN_LEFT, input->keybit); __set_bit(BTN_TOUCH, input->keybit); __set_bit(BTN_TOOL_FINGER, input->keybit); input_set_abs_params(input, ABS_X, NAVPOINT_X_MIN, NAVPOINT_X_MAX, 0, 0); input_set_abs_params(input, ABS_Y, NAVPOINT_Y_MIN, NAVPOINT_Y_MAX, 0, 0); input_set_abs_params(input, ABS_PRESSURE, NAVPOINT_PRESSURE_MIN, NAVPOINT_PRESSURE_MAX, 0, 0); input->open = navpoint_open; input->close = navpoint_close; input_set_drvdata(input, navpoint); error = request_irq(ssp->irq, navpoint_irq, 0, pdev->name, navpoint); if (error) goto err_free_mem; error = input_register_device(input); if (error) goto err_free_irq; platform_set_drvdata(pdev, navpoint); dev_dbg(&pdev->dev, "ssp%d, irq %d\n", pdata->port, ssp->irq); return 0; err_free_irq: free_irq(ssp->irq, navpoint); err_free_mem: input_free_device(input); kfree(navpoint); pxa_ssp_free(ssp); err_free_gpio: if (gpio_is_valid(pdata->gpio)) gpio_free(pdata->gpio); return error; } static int navpoint_remove(struct platform_device *pdev) { const struct navpoint_platform_data *pdata = dev_get_platdata(&pdev->dev); struct navpoint *navpoint = platform_get_drvdata(pdev); struct ssp_device *ssp = navpoint->ssp; free_irq(ssp->irq, navpoint); input_unregister_device(navpoint->input); kfree(navpoint); pxa_ssp_free(ssp); if (gpio_is_valid(pdata->gpio)) gpio_free(pdata->gpio); return 0; } static int __maybe_unused navpoint_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct navpoint *navpoint = platform_get_drvdata(pdev); struct input_dev *input = navpoint->input; mutex_lock(&input->mutex); if (input_device_enabled(input)) navpoint_down(navpoint); mutex_unlock(&input->mutex); return 0; } static int __maybe_unused navpoint_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct navpoint *navpoint = platform_get_drvdata(pdev); struct input_dev *input = navpoint->input; mutex_lock(&input->mutex); if (input_device_enabled(input)) navpoint_up(navpoint); mutex_unlock(&input->mutex); return 0; } static SIMPLE_DEV_PM_OPS(navpoint_pm_ops, navpoint_suspend, navpoint_resume); static struct platform_driver navpoint_driver = { .probe = navpoint_probe, .remove = navpoint_remove, .driver = { .name = "navpoint", .pm = &navpoint_pm_ops, }, }; module_platform_driver(navpoint_driver); MODULE_AUTHOR("Paul Parsons <lost.distance@yahoo.com>"); MODULE_DESCRIPTION("Synaptics NavPoint (PXA27x SSP/SPI) driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:navpoint");