xref: /linux/arch/arm/mach-s3c/setup-usb-phy-s3c64xx.c (revision c6ff132d4224022ffaa461ec771ec27c5319369c)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright (C) 2011 Samsung Electronics Co.Ltd
4 // Author: Joonyoung Shim <jy0922.shim@samsung.com>
5 
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/err.h>
9 #include <linux/io.h>
10 #include <linux/platform_device.h>
11 #include "map.h"
12 #include "cpu.h"
13 #include "usb-phy.h"
14 
15 #include "regs-sys-s3c64xx.h"
16 #include "regs-usb-hsotg-phy-s3c64xx.h"
17 
18 enum samsung_usb_phy_type {
19 	USB_PHY_TYPE_DEVICE,
20 	USB_PHY_TYPE_HOST,
21 };
22 
23 static int s3c_usb_otgphy_init(struct platform_device *pdev)
24 {
25 	struct clk *xusbxti;
26 	u32 phyclk;
27 
28 	writel(readl(S3C64XX_OTHERS) | S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);
29 
30 	/* set clock frequency for PLL */
31 	phyclk = readl(S3C_PHYCLK) & ~S3C_PHYCLK_CLKSEL_MASK;
32 
33 	xusbxti = clk_get(&pdev->dev, "xusbxti");
34 	if (!IS_ERR(xusbxti)) {
35 		switch (clk_get_rate(xusbxti)) {
36 		case 12 * MHZ:
37 			phyclk |= S3C_PHYCLK_CLKSEL_12M;
38 			break;
39 		case 24 * MHZ:
40 			phyclk |= S3C_PHYCLK_CLKSEL_24M;
41 			break;
42 		default:
43 		case 48 * MHZ:
44 			/* default reference clock */
45 			break;
46 		}
47 		clk_put(xusbxti);
48 	}
49 
50 	/* TODO: select external clock/oscillator */
51 	writel(phyclk | S3C_PHYCLK_CLK_FORCE, S3C_PHYCLK);
52 
53 	/* set to normal OTG PHY */
54 	writel((readl(S3C_PHYPWR) & ~S3C_PHYPWR_NORMAL_MASK), S3C_PHYPWR);
55 	mdelay(1);
56 
57 	/* reset OTG PHY and Link */
58 	writel(S3C_RSTCON_PHY | S3C_RSTCON_HCLK | S3C_RSTCON_PHYCLK,
59 			S3C_RSTCON);
60 	udelay(20);	/* at-least 10uS */
61 	writel(0, S3C_RSTCON);
62 
63 	return 0;
64 }
65 
66 static int s3c_usb_otgphy_exit(struct platform_device *pdev)
67 {
68 	writel((readl(S3C_PHYPWR) | S3C_PHYPWR_ANALOG_POWERDOWN |
69 				S3C_PHYPWR_OTG_DISABLE), S3C_PHYPWR);
70 
71 	writel(readl(S3C64XX_OTHERS) & ~S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);
72 
73 	return 0;
74 }
75 
76 int s3c_usb_phy_init(struct platform_device *pdev, int type)
77 {
78 	if (type == USB_PHY_TYPE_DEVICE)
79 		return s3c_usb_otgphy_init(pdev);
80 
81 	return -EINVAL;
82 }
83 
84 int s3c_usb_phy_exit(struct platform_device *pdev, int type)
85 {
86 	if (type == USB_PHY_TYPE_DEVICE)
87 		return s3c_usb_otgphy_exit(pdev);
88 
89 	return -EINVAL;
90 }
91