xref: /openbmc/linux/drivers/usb/musb/mpfs.c (revision e6e8c6c2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PolarFire SoC (MPFS) MUSB Glue Layer
4  *
5  * Copyright (c) 2020-2022 Microchip Corporation. All rights reserved.
6  * Based on {omap2430,tusb6010,ux500}.c
7  *
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/usb/usb_phy_generic.h>
18 #include "musb_core.h"
19 #include "musb_dma.h"
20 
21 #define MPFS_MUSB_MAX_EP_NUM	8
22 #define MPFS_MUSB_RAM_BITS	12
23 
24 struct mpfs_glue {
25 	struct device *dev;
26 	struct platform_device *musb;
27 	struct platform_device *phy;
28 	struct clk *clk;
29 };
30 
31 static struct musb_fifo_cfg mpfs_musb_mode_cfg[] = {
32 	{ .hw_ep_num = 1, .style = FIFO_TX, .maxpacket = 512, },
33 	{ .hw_ep_num = 1, .style = FIFO_RX, .maxpacket = 512, },
34 	{ .hw_ep_num = 2, .style = FIFO_TX, .maxpacket = 512, },
35 	{ .hw_ep_num = 2, .style = FIFO_RX, .maxpacket = 512, },
36 	{ .hw_ep_num = 3, .style = FIFO_TX, .maxpacket = 512, },
37 	{ .hw_ep_num = 3, .style = FIFO_RX, .maxpacket = 512, },
38 	{ .hw_ep_num = 4, .style = FIFO_TX, .maxpacket = 1024, },
39 	{ .hw_ep_num = 4, .style = FIFO_RX, .maxpacket = 4096, },
40 };
41 
42 static const struct musb_hdrc_config mpfs_musb_hdrc_config = {
43 	.fifo_cfg = mpfs_musb_mode_cfg,
44 	.fifo_cfg_size = ARRAY_SIZE(mpfs_musb_mode_cfg),
45 	.multipoint = true,
46 	.dyn_fifo = true,
47 	.num_eps = MPFS_MUSB_MAX_EP_NUM,
48 	.ram_bits = MPFS_MUSB_RAM_BITS,
49 };
50 
51 static irqreturn_t mpfs_musb_interrupt(int irq, void *__hci)
52 {
53 	unsigned long flags;
54 	irqreturn_t ret = IRQ_NONE;
55 	struct musb *musb = __hci;
56 
57 	spin_lock_irqsave(&musb->lock, flags);
58 
59 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
60 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
61 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
62 
63 	if (musb->int_usb || musb->int_tx || musb->int_rx) {
64 		musb_writeb(musb->mregs, MUSB_INTRUSB, musb->int_usb);
65 		musb_writew(musb->mregs, MUSB_INTRTX, musb->int_tx);
66 		musb_writew(musb->mregs, MUSB_INTRRX, musb->int_rx);
67 		ret = musb_interrupt(musb);
68 	}
69 
70 	spin_unlock_irqrestore(&musb->lock, flags);
71 
72 	return ret;
73 }
74 
75 static void mpfs_musb_set_vbus(struct musb *musb, int is_on)
76 {
77 	u8 devctl;
78 
79 	/*
80 	 * HDRC controls CPEN, but beware current surges during device
81 	 * connect.  They can trigger transient overcurrent conditions
82 	 * that must be ignored.
83 	 */
84 	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
85 
86 	if (is_on) {
87 		musb->is_active = 1;
88 		musb->xceiv->otg->default_a = 1;
89 		musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
90 		devctl |= MUSB_DEVCTL_SESSION;
91 		MUSB_HST_MODE(musb);
92 	} else {
93 		musb->is_active = 0;
94 
95 		/*
96 		 * NOTE:  skipping A_WAIT_VFALL -> A_IDLE and
97 		 * jumping right to B_IDLE...
98 		 */
99 		musb->xceiv->otg->default_a = 0;
100 		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
101 		devctl &= ~MUSB_DEVCTL_SESSION;
102 
103 		MUSB_DEV_MODE(musb);
104 	}
105 
106 	musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
107 
108 	dev_dbg(musb->controller, "VBUS %s, devctl %02x\n",
109 		usb_otg_state_string(musb->xceiv->otg->state),
110 		musb_readb(musb->mregs, MUSB_DEVCTL));
111 }
112 
113 static int mpfs_musb_init(struct musb *musb)
114 {
115 	struct device *dev = musb->controller;
116 
117 	musb->xceiv = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
118 	if (IS_ERR(musb->xceiv)) {
119 		dev_err(dev, "HS UDC: no transceiver configured\n");
120 		return PTR_ERR(musb->xceiv);
121 	}
122 
123 	musb->dyn_fifo = true;
124 	musb->isr = mpfs_musb_interrupt;
125 
126 	musb_platform_set_vbus(musb, 1);
127 
128 	return 0;
129 }
130 
131 static const struct musb_platform_ops mpfs_ops = {
132 	.quirks		= MUSB_DMA_INVENTRA,
133 	.init		= mpfs_musb_init,
134 	.fifo_mode	= 2,
135 #ifdef CONFIG_USB_INVENTRA_DMA
136 	.dma_init	= musbhs_dma_controller_create,
137 	.dma_exit	= musbhs_dma_controller_destroy,
138 #endif
139 	.set_vbus	= mpfs_musb_set_vbus
140 };
141 
142 static int mpfs_probe(struct platform_device *pdev)
143 {
144 	struct musb_hdrc_platform_data *pdata = dev_get_platdata(&pdev->dev);
145 	struct mpfs_glue *glue;
146 	struct platform_device *musb_pdev;
147 	struct device *dev = &pdev->dev;
148 	struct clk *clk;
149 	int ret;
150 
151 	glue = devm_kzalloc(dev, sizeof(*glue), GFP_KERNEL);
152 	if (!glue)
153 		return -ENOMEM;
154 
155 	musb_pdev = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
156 	if (!musb_pdev) {
157 		dev_err(dev, "failed to allocate musb device\n");
158 		return -ENOMEM;
159 	}
160 
161 	clk = devm_clk_get(&pdev->dev, NULL);
162 	if (IS_ERR(clk)) {
163 		dev_err(&pdev->dev, "failed to get clock\n");
164 		ret = PTR_ERR(clk);
165 		goto err_phy_release;
166 	}
167 
168 	ret = clk_prepare_enable(clk);
169 	if (ret) {
170 		dev_err(&pdev->dev, "failed to enable clock\n");
171 		goto err_phy_release;
172 	}
173 
174 	musb_pdev->dev.parent = dev;
175 	musb_pdev->dev.coherent_dma_mask = DMA_BIT_MASK(39);
176 	musb_pdev->dev.dma_mask = &musb_pdev->dev.coherent_dma_mask;
177 	device_set_of_node_from_dev(&musb_pdev->dev, dev);
178 
179 	glue->dev = dev;
180 	glue->musb = musb_pdev;
181 	glue->clk = clk;
182 
183 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
184 	if (!pdata) {
185 		ret = -ENOMEM;
186 		goto err_clk_disable;
187 	}
188 
189 	pdata->config = &mpfs_musb_hdrc_config;
190 	pdata->platform_ops = &mpfs_ops;
191 
192 	pdata->mode = usb_get_dr_mode(dev);
193 	if (pdata->mode == USB_DR_MODE_UNKNOWN) {
194 		dev_info(dev, "No dr_mode property found, defaulting to otg\n");
195 		pdata->mode = USB_DR_MODE_OTG;
196 	}
197 
198 	glue->phy = usb_phy_generic_register();
199 	if (IS_ERR(glue->phy)) {
200 		dev_err(dev, "failed to register usb-phy %ld\n",
201 			PTR_ERR(glue->phy));
202 		ret = PTR_ERR(glue->phy);
203 		goto err_clk_disable;
204 	}
205 
206 	platform_set_drvdata(pdev, glue);
207 
208 	ret = platform_device_add_resources(musb_pdev, pdev->resource, pdev->num_resources);
209 	if (ret) {
210 		dev_err(dev, "failed to add resources\n");
211 		goto err_clk_disable;
212 	}
213 
214 	ret = platform_device_add_data(musb_pdev, pdata, sizeof(*pdata));
215 	if (ret) {
216 		dev_err(dev, "failed to add platform_data\n");
217 		goto err_clk_disable;
218 	}
219 
220 	ret = platform_device_add(musb_pdev);
221 	if (ret) {
222 		dev_err(dev, "failed to register musb device\n");
223 		goto err_clk_disable;
224 	}
225 
226 	dev_info(&pdev->dev, "Registered MPFS MUSB driver\n");
227 	return 0;
228 
229 err_clk_disable:
230 	clk_disable_unprepare(clk);
231 
232 err_phy_release:
233 	usb_phy_generic_unregister(glue->phy);
234 	platform_device_put(musb_pdev);
235 	return ret;
236 }
237 
238 static int mpfs_remove(struct platform_device *pdev)
239 {
240 	struct mpfs_glue *glue = platform_get_drvdata(pdev);
241 
242 	clk_disable_unprepare(glue->clk);
243 	platform_device_unregister(glue->musb);
244 	usb_phy_generic_unregister(pdev);
245 
246 	return 0;
247 }
248 
249 #ifdef CONFIG_OF
250 static const struct of_device_id mpfs_id_table[] = {
251 	{ .compatible = "microchip,mpfs-musb" },
252 	{ }
253 };
254 MODULE_DEVICE_TABLE(of, mpfs_id_table);
255 #endif
256 
257 static struct platform_driver mpfs_musb_driver = {
258 	.probe = mpfs_probe,
259 	.remove = mpfs_remove,
260 	.driver = {
261 		.name = "mpfs-musb",
262 		.of_match_table = of_match_ptr(mpfs_id_table)
263 	},
264 };
265 
266 module_platform_driver(mpfs_musb_driver);
267 
268 MODULE_DESCRIPTION("PolarFire SoC MUSB Glue Layer");
269 MODULE_LICENSE("GPL");
270