diff options
Diffstat (limited to 'drivers/phy/phy-bcm-ns-usb2.c')
-rw-r--r-- | drivers/phy/phy-bcm-ns-usb2.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/phy/phy-bcm-ns-usb2.c b/drivers/phy/phy-bcm-ns-usb2.c new file mode 100644 index 000000000000..95ab6b2a0de5 --- /dev/null +++ b/drivers/phy/phy-bcm-ns-usb2.c | |||
@@ -0,0 +1,137 @@ | |||
1 | /* | ||
2 | * Broadcom Northstar USB 2.0 PHY Driver | ||
3 | * | ||
4 | * Copyright (C) 2016 Rafał Miłecki <zajec5@gmail.com> | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License version 2 as | ||
8 | * published by the Free Software Foundation. | ||
9 | * | ||
10 | */ | ||
11 | |||
12 | #include <linux/bcma/bcma.h> | ||
13 | #include <linux/clk.h> | ||
14 | #include <linux/delay.h> | ||
15 | #include <linux/err.h> | ||
16 | #include <linux/module.h> | ||
17 | #include <linux/of_address.h> | ||
18 | #include <linux/of_platform.h> | ||
19 | #include <linux/phy/phy.h> | ||
20 | #include <linux/platform_device.h> | ||
21 | #include <linux/slab.h> | ||
22 | |||
23 | struct bcm_ns_usb2 { | ||
24 | struct device *dev; | ||
25 | struct clk *ref_clk; | ||
26 | struct phy *phy; | ||
27 | void __iomem *dmu; | ||
28 | }; | ||
29 | |||
30 | static int bcm_ns_usb2_phy_init(struct phy *phy) | ||
31 | { | ||
32 | struct bcm_ns_usb2 *usb2 = phy_get_drvdata(phy); | ||
33 | struct device *dev = usb2->dev; | ||
34 | void __iomem *dmu = usb2->dmu; | ||
35 | u32 ref_clk_rate, usb2ctl, usb_pll_ndiv, usb_pll_pdiv; | ||
36 | int err = 0; | ||
37 | |||
38 | err = clk_prepare_enable(usb2->ref_clk); | ||
39 | if (err < 0) { | ||
40 | dev_err(dev, "Failed to prepare ref clock: %d\n", err); | ||
41 | goto err_out; | ||
42 | } | ||
43 | |||
44 | ref_clk_rate = clk_get_rate(usb2->ref_clk); | ||
45 | if (!ref_clk_rate) { | ||
46 | dev_err(dev, "Failed to get ref clock rate\n"); | ||
47 | err = -EINVAL; | ||
48 | goto err_clk_off; | ||
49 | } | ||
50 | |||
51 | usb2ctl = readl(dmu + BCMA_DMU_CRU_USB2_CONTROL); | ||
52 | |||
53 | if (usb2ctl & BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK) { | ||
54 | usb_pll_pdiv = usb2ctl; | ||
55 | usb_pll_pdiv &= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK; | ||
56 | usb_pll_pdiv >>= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT; | ||
57 | } else { | ||
58 | usb_pll_pdiv = 1 << 3; | ||
59 | } | ||
60 | |||
61 | /* Calculate ndiv based on a solid 1920 MHz that is for USB2 PHY */ | ||
62 | usb_pll_ndiv = (1920000000 * usb_pll_pdiv) / ref_clk_rate; | ||
63 | |||
64 | /* Unlock DMU PLL settings with some magic value */ | ||
65 | writel(0x0000ea68, dmu + BCMA_DMU_CRU_CLKSET_KEY); | ||
66 | |||
67 | /* Write USB 2.0 PLL control setting */ | ||
68 | usb2ctl &= ~BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK; | ||
69 | usb2ctl |= usb_pll_ndiv << BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT; | ||
70 | writel(usb2ctl, dmu + BCMA_DMU_CRU_USB2_CONTROL); | ||
71 | |||
72 | /* Lock DMU PLL settings */ | ||
73 | writel(0x00000000, dmu + BCMA_DMU_CRU_CLKSET_KEY); | ||
74 | |||
75 | err_clk_off: | ||
76 | clk_disable_unprepare(usb2->ref_clk); | ||
77 | err_out: | ||
78 | return err; | ||
79 | } | ||
80 | |||
81 | static const struct phy_ops ops = { | ||
82 | .init = bcm_ns_usb2_phy_init, | ||
83 | .owner = THIS_MODULE, | ||
84 | }; | ||
85 | |||
86 | static int bcm_ns_usb2_probe(struct platform_device *pdev) | ||
87 | { | ||
88 | struct device *dev = &pdev->dev; | ||
89 | struct bcm_ns_usb2 *usb2; | ||
90 | struct resource *res; | ||
91 | struct phy_provider *phy_provider; | ||
92 | |||
93 | usb2 = devm_kzalloc(&pdev->dev, sizeof(*usb2), GFP_KERNEL); | ||
94 | if (!usb2) | ||
95 | return -ENOMEM; | ||
96 | usb2->dev = dev; | ||
97 | |||
98 | res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dmu"); | ||
99 | usb2->dmu = devm_ioremap_resource(dev, res); | ||
100 | if (IS_ERR(usb2->dmu)) { | ||
101 | dev_err(dev, "Failed to map DMU regs\n"); | ||
102 | return PTR_ERR(usb2->dmu); | ||
103 | } | ||
104 | |||
105 | usb2->ref_clk = devm_clk_get(dev, "phy-ref-clk"); | ||
106 | if (IS_ERR(usb2->ref_clk)) { | ||
107 | dev_err(dev, "Clock not defined\n"); | ||
108 | return PTR_ERR(usb2->ref_clk); | ||
109 | } | ||
110 | |||
111 | usb2->phy = devm_phy_create(dev, NULL, &ops); | ||
112 | if (IS_ERR(dev)) | ||
113 | return PTR_ERR(dev); | ||
114 | |||
115 | phy_set_drvdata(usb2->phy, usb2); | ||
116 | platform_set_drvdata(pdev, usb2); | ||
117 | |||
118 | phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); | ||
119 | return PTR_ERR_OR_ZERO(phy_provider); | ||
120 | } | ||
121 | |||
122 | static const struct of_device_id bcm_ns_usb2_id_table[] = { | ||
123 | { .compatible = "brcm,ns-usb2-phy", }, | ||
124 | {}, | ||
125 | }; | ||
126 | MODULE_DEVICE_TABLE(of, bcm_ns_usb2_id_table); | ||
127 | |||
128 | static struct platform_driver bcm_ns_usb2_driver = { | ||
129 | .probe = bcm_ns_usb2_probe, | ||
130 | .driver = { | ||
131 | .name = "bcm_ns_usb2", | ||
132 | .of_match_table = bcm_ns_usb2_id_table, | ||
133 | }, | ||
134 | }; | ||
135 | module_platform_driver(bcm_ns_usb2_driver); | ||
136 | |||
137 | MODULE_LICENSE("GPL v2"); | ||