xref: /openbmc/linux/drivers/usb/renesas_usbhs/rza.c (revision 484468fb)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas USB driver RZ/A initialization and power control
4  *
5  * Copyright (C) 2018 Chris Brandt
6  * Copyright (C) 2018-2019 Renesas Electronics Corporation
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/of.h>
12 #include "common.h"
13 #include "rza.h"
14 
usbhs_rza1_hardware_init(struct platform_device * pdev)15 static int usbhs_rza1_hardware_init(struct platform_device *pdev)
16 {
17 	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
18 	struct device_node *usb_x1_clk, *extal_clk;
19 	u32 freq_usb = 0, freq_extal = 0;
20 
21 	/* Input Clock Selection (NOTE: ch0 controls both ch0 and ch1) */
22 	usb_x1_clk = of_find_node_by_name(NULL, "usb_x1");
23 	extal_clk = of_find_node_by_name(NULL, "extal");
24 	of_property_read_u32(usb_x1_clk, "clock-frequency", &freq_usb);
25 	of_property_read_u32(extal_clk, "clock-frequency", &freq_extal);
26 
27 	of_node_put(usb_x1_clk);
28 	of_node_put(extal_clk);
29 
30 	if (freq_usb == 0) {
31 		if (freq_extal == 12000000) {
32 			/* Select 12MHz XTAL */
33 			usbhs_bset(priv, SYSCFG, UCKSEL, UCKSEL);
34 		} else {
35 			dev_err(usbhs_priv_to_dev(priv), "A 48MHz USB clock or 12MHz main clock is required.\n");
36 			return -EIO;
37 		}
38 	}
39 
40 	/* Enable USB PLL (NOTE: ch0 controls both ch0 and ch1) */
41 	usbhs_bset(priv, SYSCFG, UPLLE, UPLLE);
42 	usleep_range(1000, 2000);
43 	usbhs_bset(priv, SUSPMODE, SUSPM, SUSPM);
44 
45 	return 0;
46 }
47 
48 const struct renesas_usbhs_platform_info usbhs_rza1_plat_info = {
49 	.platform_callback = {
50 		.hardware_init = usbhs_rza1_hardware_init,
51 		.get_id = usbhs_get_id_as_gadget,
52 	},
53 	.driver_param = {
54 		.has_new_pipe_configs = 1,
55 	},
56 };
57