| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * TI Touch Screen / ADC MFD driver | 
 |  * | 
 |  * Copyright (C) 2012 Texas Instruments Incorporated - https://www.ti.com/ | 
 |  */ | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/err.h> | 
 | #include <linux/io.h> | 
 | #include <linux/clk.h> | 
 | #include <linux/regmap.h> | 
 | #include <linux/mfd/core.h> | 
 | #include <linux/pm_runtime.h> | 
 | #include <linux/of.h> | 
 | #include <linux/of_device.h> | 
 | #include <linux/sched.h> | 
 |  | 
 | #include <linux/mfd/ti_am335x_tscadc.h> | 
 |  | 
 | static const struct regmap_config tscadc_regmap_config = { | 
 | 	.name = "ti_tscadc", | 
 | 	.reg_bits = 32, | 
 | 	.reg_stride = 4, | 
 | 	.val_bits = 32, | 
 | }; | 
 |  | 
 | void am335x_tsc_se_set_cache(struct ti_tscadc_dev *tscadc, u32 val) | 
 | { | 
 | 	unsigned long flags; | 
 |  | 
 | 	spin_lock_irqsave(&tscadc->reg_lock, flags); | 
 | 	tscadc->reg_se_cache |= val; | 
 | 	if (tscadc->adc_waiting) | 
 | 		wake_up(&tscadc->reg_se_wait); | 
 | 	else if (!tscadc->adc_in_use) | 
 | 		regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache); | 
 |  | 
 | 	spin_unlock_irqrestore(&tscadc->reg_lock, flags); | 
 | } | 
 | EXPORT_SYMBOL_GPL(am335x_tsc_se_set_cache); | 
 |  | 
 | static void am335x_tscadc_need_adc(struct ti_tscadc_dev *tscadc) | 
 | { | 
 | 	DEFINE_WAIT(wait); | 
 | 	u32 reg; | 
 |  | 
 | 	regmap_read(tscadc->regmap, REG_ADCFSM, ®); | 
 | 	if (reg & SEQ_STATUS) { | 
 | 		tscadc->adc_waiting = true; | 
 | 		prepare_to_wait(&tscadc->reg_se_wait, &wait, | 
 | 				TASK_UNINTERRUPTIBLE); | 
 | 		spin_unlock_irq(&tscadc->reg_lock); | 
 |  | 
 | 		schedule(); | 
 |  | 
 | 		spin_lock_irq(&tscadc->reg_lock); | 
 | 		finish_wait(&tscadc->reg_se_wait, &wait); | 
 |  | 
 | 		/* | 
 | 		 * Sequencer should either be idle or | 
 | 		 * busy applying the charge step. | 
 | 		 */ | 
 | 		regmap_read(tscadc->regmap, REG_ADCFSM, ®); | 
 | 		WARN_ON((reg & SEQ_STATUS) && !(reg & CHARGE_STEP)); | 
 | 		tscadc->adc_waiting = false; | 
 | 	} | 
 | 	tscadc->adc_in_use = true; | 
 | } | 
 |  | 
 | void am335x_tsc_se_set_once(struct ti_tscadc_dev *tscadc, u32 val) | 
 | { | 
 | 	spin_lock_irq(&tscadc->reg_lock); | 
 | 	am335x_tscadc_need_adc(tscadc); | 
 |  | 
 | 	regmap_write(tscadc->regmap, REG_SE, val); | 
 | 	spin_unlock_irq(&tscadc->reg_lock); | 
 | } | 
 | EXPORT_SYMBOL_GPL(am335x_tsc_se_set_once); | 
 |  | 
 | void am335x_tsc_se_adc_done(struct ti_tscadc_dev *tscadc) | 
 | { | 
 | 	unsigned long flags; | 
 |  | 
 | 	spin_lock_irqsave(&tscadc->reg_lock, flags); | 
 | 	tscadc->adc_in_use = false; | 
 | 	regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache); | 
 | 	spin_unlock_irqrestore(&tscadc->reg_lock, flags); | 
 | } | 
 | EXPORT_SYMBOL_GPL(am335x_tsc_se_adc_done); | 
 |  | 
 | void am335x_tsc_se_clr(struct ti_tscadc_dev *tscadc, u32 val) | 
 | { | 
 | 	unsigned long flags; | 
 |  | 
 | 	spin_lock_irqsave(&tscadc->reg_lock, flags); | 
 | 	tscadc->reg_se_cache &= ~val; | 
 | 	regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache); | 
 | 	spin_unlock_irqrestore(&tscadc->reg_lock, flags); | 
 | } | 
 | EXPORT_SYMBOL_GPL(am335x_tsc_se_clr); | 
 |  | 
 | static void tscadc_idle_config(struct ti_tscadc_dev *tscadc) | 
 | { | 
 | 	unsigned int idleconfig; | 
 |  | 
 | 	idleconfig = STEPCONFIG_INM_ADCREFM | STEPCONFIG_INP_ADCREFM; | 
 | 	if (ti_adc_with_touchscreen(tscadc)) | 
 | 		idleconfig |= STEPCONFIG_YNN | STEPCONFIG_YPN; | 
 |  | 
 | 	regmap_write(tscadc->regmap, REG_IDLECONFIG, idleconfig); | 
 | } | 
 |  | 
 | static	int ti_tscadc_probe(struct platform_device *pdev) | 
 | { | 
 | 	struct ti_tscadc_dev *tscadc; | 
 | 	struct resource *res; | 
 | 	struct clk *clk; | 
 | 	struct device_node *node; | 
 | 	struct mfd_cell *cell; | 
 | 	struct property *prop; | 
 | 	const __be32 *cur; | 
 | 	bool use_tsc = false, use_mag = false; | 
 | 	u32 val; | 
 | 	int err; | 
 | 	int tscmag_wires = 0, adc_channels = 0, cell_idx = 0, total_channels; | 
 | 	int readouts = 0, mag_tracks = 0; | 
 |  | 
 | 	/* Allocate memory for device */ | 
 | 	tscadc = devm_kzalloc(&pdev->dev, sizeof(*tscadc), GFP_KERNEL); | 
 | 	if (!tscadc) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	tscadc->dev = &pdev->dev; | 
 |  | 
 | 	if (!pdev->dev.of_node) { | 
 | 		dev_err(&pdev->dev, "Could not find valid DT data.\n"); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	tscadc->data = of_device_get_match_data(&pdev->dev); | 
 |  | 
 | 	if (ti_adc_with_touchscreen(tscadc)) { | 
 | 		node = of_get_child_by_name(pdev->dev.of_node, "tsc"); | 
 | 		of_property_read_u32(node, "ti,wires", &tscmag_wires); | 
 | 		err = of_property_read_u32(node, "ti,coordinate-readouts", | 
 | 					   &readouts); | 
 | 		if (err < 0) | 
 | 			of_property_read_u32(node, "ti,coordiante-readouts", | 
 | 					     &readouts); | 
 |  | 
 | 		of_node_put(node); | 
 |  | 
 | 		if (tscmag_wires) | 
 | 			use_tsc = true; | 
 | 	} else { | 
 | 		/* | 
 | 		 * When adding support for the magnetic stripe reader, here is | 
 | 		 * the place to look for the number of tracks used from device | 
 | 		 * tree. Let's default to 0 for now. | 
 | 		 */ | 
 | 		mag_tracks = 0; | 
 | 		tscmag_wires = mag_tracks * 2; | 
 | 		if (tscmag_wires) | 
 | 			use_mag = true; | 
 | 	} | 
 |  | 
 | 	node = of_get_child_by_name(pdev->dev.of_node, "adc"); | 
 | 	of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) { | 
 | 		adc_channels++; | 
 | 		if (val > 7) { | 
 | 			dev_err(&pdev->dev, " PIN numbers are 0..7 (not %d)\n", | 
 | 				val); | 
 | 			of_node_put(node); | 
 | 			return -EINVAL; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	of_node_put(node); | 
 |  | 
 | 	total_channels = tscmag_wires + adc_channels; | 
 | 	if (total_channels > 8) { | 
 | 		dev_err(&pdev->dev, "Number of i/p channels more than 8\n"); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	if (total_channels == 0) { | 
 | 		dev_err(&pdev->dev, "Need at least one channel.\n"); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	if (use_tsc && (readouts * 2 + 2 + adc_channels > 16)) { | 
 | 		dev_err(&pdev->dev, "Too many step configurations requested\n"); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	err = platform_get_irq(pdev, 0); | 
 | 	if (err < 0) | 
 | 		return err; | 
 | 	else | 
 | 		tscadc->irq = err; | 
 |  | 
 | 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | 
 | 	tscadc->tscadc_base = devm_ioremap_resource(&pdev->dev, res); | 
 | 	if (IS_ERR(tscadc->tscadc_base)) | 
 | 		return PTR_ERR(tscadc->tscadc_base); | 
 |  | 
 | 	tscadc->tscadc_phys_base = res->start; | 
 | 	tscadc->regmap = devm_regmap_init_mmio(&pdev->dev, | 
 | 					       tscadc->tscadc_base, | 
 | 					       &tscadc_regmap_config); | 
 | 	if (IS_ERR(tscadc->regmap)) { | 
 | 		dev_err(&pdev->dev, "regmap init failed\n"); | 
 | 		return PTR_ERR(tscadc->regmap); | 
 | 	} | 
 |  | 
 | 	spin_lock_init(&tscadc->reg_lock); | 
 | 	init_waitqueue_head(&tscadc->reg_se_wait); | 
 |  | 
 | 	pm_runtime_enable(&pdev->dev); | 
 | 	pm_runtime_get_sync(&pdev->dev); | 
 |  | 
 | 	/* | 
 | 	 * The TSC_ADC_Subsystem has 2 clock domains: OCP_CLK and ADC_CLK. | 
 | 	 * ADCs produce a 12-bit sample every 15 ADC_CLK cycles. | 
 | 	 * am33xx ADCs expect to capture 200ksps. | 
 | 	 * am47xx ADCs expect to capture 867ksps. | 
 | 	 * We need ADC clocks respectively running at 3MHz and 13MHz. | 
 | 	 * These frequencies are valid since TSC_ADC_SS controller design | 
 | 	 * assumes the OCP clock is at least 6x faster than the ADC clock. | 
 | 	 */ | 
 | 	clk = devm_clk_get(&pdev->dev, NULL); | 
 | 	if (IS_ERR(clk)) { | 
 | 		dev_err(&pdev->dev, "failed to get fck\n"); | 
 | 		err = PTR_ERR(clk); | 
 | 		goto err_disable_clk; | 
 | 	} | 
 |  | 
 | 	tscadc->clk_div = (clk_get_rate(clk) / tscadc->data->target_clk_rate) - 1; | 
 | 	regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); | 
 |  | 
 | 	/* | 
 | 	 * Set the control register bits. tscadc->ctrl stores the configuration | 
 | 	 * of the CTRL register but not the subsystem enable bit which must be | 
 | 	 * added manually when timely. | 
 | 	 */ | 
 | 	tscadc->ctrl = CNTRLREG_STEPID; | 
 | 	if (ti_adc_with_touchscreen(tscadc)) { | 
 | 		tscadc->ctrl |= CNTRLREG_TSC_STEPCONFIGWRT; | 
 | 		if (use_tsc) { | 
 | 			tscadc->ctrl |= CNTRLREG_TSC_ENB; | 
 | 			if (tscmag_wires == 5) | 
 | 				tscadc->ctrl |= CNTRLREG_TSC_5WIRE; | 
 | 			else | 
 | 				tscadc->ctrl |= CNTRLREG_TSC_4WIRE; | 
 | 		} | 
 | 	} else { | 
 | 		tscadc->ctrl |= CNTRLREG_MAG_PREAMP_PWRDOWN | | 
 | 				CNTRLREG_MAG_PREAMP_BYPASS; | 
 | 	} | 
 | 	regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl); | 
 |  | 
 | 	tscadc_idle_config(tscadc); | 
 |  | 
 | 	/* Enable the TSC module enable bit */ | 
 | 	regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_SSENB); | 
 |  | 
 | 	/* TSC or MAG Cell */ | 
 | 	if (use_tsc || use_mag) { | 
 | 		cell = &tscadc->cells[cell_idx++]; | 
 | 		cell->name = tscadc->data->secondary_feature_name; | 
 | 		cell->of_compatible = tscadc->data->secondary_feature_compatible; | 
 | 		cell->platform_data = &tscadc; | 
 | 		cell->pdata_size = sizeof(tscadc); | 
 | 	} | 
 |  | 
 | 	/* ADC Cell */ | 
 | 	if (adc_channels > 0) { | 
 | 		cell = &tscadc->cells[cell_idx++]; | 
 | 		cell->name = tscadc->data->adc_feature_name; | 
 | 		cell->of_compatible = tscadc->data->adc_feature_compatible; | 
 | 		cell->platform_data = &tscadc; | 
 | 		cell->pdata_size = sizeof(tscadc); | 
 | 	} | 
 |  | 
 | 	err = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, | 
 | 			      tscadc->cells, cell_idx, NULL, 0, NULL); | 
 | 	if (err < 0) | 
 | 		goto err_disable_clk; | 
 |  | 
 | 	platform_set_drvdata(pdev, tscadc); | 
 | 	return 0; | 
 |  | 
 | err_disable_clk: | 
 | 	pm_runtime_put_sync(&pdev->dev); | 
 | 	pm_runtime_disable(&pdev->dev); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | static int ti_tscadc_remove(struct platform_device *pdev) | 
 | { | 
 | 	struct ti_tscadc_dev *tscadc = platform_get_drvdata(pdev); | 
 |  | 
 | 	regmap_write(tscadc->regmap, REG_SE, 0x00); | 
 |  | 
 | 	pm_runtime_put_sync(&pdev->dev); | 
 | 	pm_runtime_disable(&pdev->dev); | 
 |  | 
 | 	mfd_remove_devices(tscadc->dev); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int __maybe_unused ti_tscadc_can_wakeup(struct device *dev, void *data) | 
 | { | 
 | 	return device_may_wakeup(dev); | 
 | } | 
 |  | 
 | static int __maybe_unused tscadc_suspend(struct device *dev) | 
 | { | 
 | 	struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev); | 
 |  | 
 | 	regmap_write(tscadc->regmap, REG_SE, 0x00); | 
 | 	if (device_for_each_child(dev, NULL, ti_tscadc_can_wakeup)) { | 
 | 		u32 ctrl; | 
 |  | 
 | 		regmap_read(tscadc->regmap, REG_CTRL, &ctrl); | 
 | 		ctrl &= ~(CNTRLREG_POWERDOWN); | 
 | 		ctrl |= CNTRLREG_SSENB; | 
 | 		regmap_write(tscadc->regmap, REG_CTRL, ctrl); | 
 | 	} | 
 | 	pm_runtime_put_sync(dev); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int __maybe_unused tscadc_resume(struct device *dev) | 
 | { | 
 | 	struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev); | 
 |  | 
 | 	pm_runtime_get_sync(dev); | 
 |  | 
 | 	regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); | 
 | 	regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl); | 
 | 	tscadc_idle_config(tscadc); | 
 | 	regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_SSENB); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static SIMPLE_DEV_PM_OPS(tscadc_pm_ops, tscadc_suspend, tscadc_resume); | 
 |  | 
 | static const struct ti_tscadc_data tscdata = { | 
 | 	.adc_feature_name = "TI-am335x-adc", | 
 | 	.adc_feature_compatible = "ti,am3359-adc", | 
 | 	.secondary_feature_name = "TI-am335x-tsc", | 
 | 	.secondary_feature_compatible = "ti,am3359-tsc", | 
 | 	.target_clk_rate = TSC_ADC_CLK, | 
 | }; | 
 |  | 
 | static const struct ti_tscadc_data magdata = { | 
 | 	.adc_feature_name = "TI-am43xx-adc", | 
 | 	.adc_feature_compatible = "ti,am4372-adc", | 
 | 	.secondary_feature_name = "TI-am43xx-mag", | 
 | 	.secondary_feature_compatible = "ti,am4372-mag", | 
 | 	.target_clk_rate = MAG_ADC_CLK, | 
 | }; | 
 |  | 
 | static const struct of_device_id ti_tscadc_dt_ids[] = { | 
 | 	{ .compatible = "ti,am3359-tscadc", .data = &tscdata }, | 
 | 	{ .compatible = "ti,am4372-magadc", .data = &magdata }, | 
 | 	{ } | 
 | }; | 
 | MODULE_DEVICE_TABLE(of, ti_tscadc_dt_ids); | 
 |  | 
 | static struct platform_driver ti_tscadc_driver = { | 
 | 	.driver = { | 
 | 		.name   = "ti_am3359-tscadc", | 
 | 		.pm	= &tscadc_pm_ops, | 
 | 		.of_match_table = ti_tscadc_dt_ids, | 
 | 	}, | 
 | 	.probe	= ti_tscadc_probe, | 
 | 	.remove	= ti_tscadc_remove, | 
 |  | 
 | }; | 
 |  | 
 | module_platform_driver(ti_tscadc_driver); | 
 |  | 
 | MODULE_DESCRIPTION("TI touchscreen/magnetic stripe reader/ADC MFD controller driver"); | 
 | MODULE_AUTHOR("Rachna Patil <rachna@ti.com>"); | 
 | MODULE_LICENSE("GPL"); |