1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Driver for the MMC / SD / SDIO cell found in:
  4 *
  5 * TC6393XB TC6391XB TC6387XB T7L66XB ASIC3
  6 *
  7 * Copyright (C) 2017 Renesas Electronics Corporation
  8 * Copyright (C) 2017 Horms Solutions, Simon Horman
  9 * Copyright (C) 2007 Ian Molton
 10 * Copyright (C) 2004 Ian Molton
 11 */
 12
 13#include <linux/delay.h>
 14#include <linux/device.h>
 15#include <linux/mfd/core.h>
 16#include <linux/mfd/tmio.h>
 17#include <linux/mmc/host.h>
 18#include <linux/module.h>
 19#include <linux/pagemap.h>
 20#include <linux/scatterlist.h>
 21
 22#include "tmio_mmc.h"
 23
 24/* Registers specific to this variant */
 25#define CTL_SDIO_REGS		0x100
 26#define CTL_CLK_AND_WAIT_CTL	0x138
 27#define CTL_RESET_SDIO		0x1e0
 28
 29static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
 30{
 31	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
 32		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
 33
 34	usleep_range(10000, 11000);
 35	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
 36	usleep_range(10000, 11000);
 37}
 38
 39static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
 40{
 41	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
 42	usleep_range(10000, 11000);
 43
 44	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
 45		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
 46
 47	usleep_range(10000, 11000);
 48}
 49
 50static void tmio_mmc_set_clock(struct tmio_mmc_host *host,
 51			       unsigned int new_clock)
 52{
 53	unsigned int divisor;
 54	u32 clk = 0;
 55	int clk_sel;
 56
 57	if (new_clock == 0) {
 58		tmio_mmc_clk_stop(host);
 59		return;
 60	}
 61
 62	divisor = host->pdata->hclk / new_clock;
 63
 64	/* bit7 set: 1/512, ... bit0 set: 1/4, all bits clear: 1/2 */
 65	clk_sel = (divisor <= 1);
 66	clk = clk_sel ? 0 : (roundup_pow_of_two(divisor) >> 2);
 67
 68	host->pdata->set_clk_div(host->pdev, clk_sel);
 69
 70	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
 71			sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
 72	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & CLK_CTL_DIV_MASK);
 73	usleep_range(10000, 11000);
 74
 75	tmio_mmc_clk_start(host);
 76}
 77
 78static void tmio_mmc_reset(struct tmio_mmc_host *host, bool preserve)
 79{
 80	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
 81	usleep_range(10000, 11000);
 82	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
 83	usleep_range(10000, 11000);
 84}
 85
 86#ifdef CONFIG_PM_SLEEP
 87static int tmio_mmc_suspend(struct device *dev)
 88{
 89	struct platform_device *pdev = to_platform_device(dev);
 90	const struct mfd_cell *cell = mfd_get_cell(pdev);
 91	int ret;
 92
 93	ret = pm_runtime_force_suspend(dev);
 94
 95	/* Tell MFD core it can disable us now.*/
 96	if (!ret && cell->disable)
 97		cell->disable(pdev);
 98
 99	return ret;
100}
101
102static int tmio_mmc_resume(struct device *dev)
103{
104	struct platform_device *pdev = to_platform_device(dev);
105	const struct mfd_cell *cell = mfd_get_cell(pdev);
106	int ret = 0;
107
108	/* Tell the MFD core we are ready to be enabled */
109	if (cell->resume)
110		ret = cell->resume(pdev);
111
112	if (!ret)
113		ret = pm_runtime_force_resume(dev);
114
115	return ret;
116}
117#endif
118
119static int tmio_mmc_probe(struct platform_device *pdev)
120{
121	const struct mfd_cell *cell = mfd_get_cell(pdev);
122	struct tmio_mmc_data *pdata;
123	struct tmio_mmc_host *host;
124	struct resource *res;
125	int ret = -EINVAL, irq;
126
127	if (pdev->num_resources != 2)
128		goto out;
129
130	pdata = pdev->dev.platform_data;
131	if (!pdata || !pdata->hclk)
132		goto out;
133
134	irq = platform_get_irq(pdev, 0);
135	if (irq < 0) {
136		ret = irq;
137		goto out;
138	}
139
140	/* Tell the MFD core we are ready to be enabled */
141	if (cell->enable) {
142		ret = cell->enable(pdev);
143		if (ret)
144			goto out;
145	}
146
147	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
148	if (!res) {
149		ret = -EINVAL;
150		goto cell_disable;
151	}
152
153	host = tmio_mmc_host_alloc(pdev, pdata);
154	if (IS_ERR(host)) {
155		ret = PTR_ERR(host);
156		goto cell_disable;
157	}
158
159	/* SD control register space size is 0x200, 0x400 for bus_shift=1 */
160	host->bus_shift = resource_size(res) >> 10;
161	host->set_clock = tmio_mmc_set_clock;
162	host->reset = tmio_mmc_reset;
163
164	host->mmc->f_max = pdata->hclk;
165	host->mmc->f_min = pdata->hclk / 512;
166
167	ret = tmio_mmc_host_probe(host);
168	if (ret)
169		goto host_free;
170
171	ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq,
172			       IRQF_TRIGGER_FALLING,
173			       dev_name(&pdev->dev), host);
174	if (ret)
175		goto host_remove;
176
177	pr_info("%s at 0x%p irq %d\n", mmc_hostname(host->mmc), host->ctl, irq);
178
179	return 0;
180
181host_remove:
182	tmio_mmc_host_remove(host);
183host_free:
184	tmio_mmc_host_free(host);
185cell_disable:
186	if (cell->disable)
187		cell->disable(pdev);
188out:
189	return ret;
190}
191
192static int tmio_mmc_remove(struct platform_device *pdev)
193{
194	const struct mfd_cell *cell = mfd_get_cell(pdev);
195	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
196
197	tmio_mmc_host_remove(host);
198	if (cell->disable)
199		cell->disable(pdev);
200
201	return 0;
202}
203
204/* ------------------- device registration ----------------------- */
205
206static const struct dev_pm_ops tmio_mmc_dev_pm_ops = {
207	SET_SYSTEM_SLEEP_PM_OPS(tmio_mmc_suspend, tmio_mmc_resume)
208	SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
209			   tmio_mmc_host_runtime_resume, NULL)
210};
211
212static struct platform_driver tmio_mmc_driver = {
213	.driver = {
214		.name = "tmio-mmc",
215		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
216		.pm = &tmio_mmc_dev_pm_ops,
217	},
218	.probe = tmio_mmc_probe,
219	.remove = tmio_mmc_remove,
220};
221
222module_platform_driver(tmio_mmc_driver);
223
224MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
225MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
226MODULE_LICENSE("GPL v2");
227MODULE_ALIAS("platform:tmio-mmc");