[V6 PATCH 01/16] usb: phy: mv_usb2: add PHY driver for marvell usb2 controller
Chao Xie
xiechao.mail at gmail.com
Wed Feb 6 21:26:58 EST 2013
On Wed, Feb 6, 2013 at 6:35 PM, kishon <kishon at ti.com> wrote:
> Hi,
>
>
> On Wednesday 06 February 2013 01:48 PM, Chao Xie wrote:
>>
>> On Wed, Feb 6, 2013 at 4:10 PM, kishon <kishon at ti.com> wrote:
>>>
>>> Hi,
>>>
>>>
>>> On Wednesday 06 February 2013 12:53 PM, Chao Xie wrote:
>>>>
>>>>
>>>> The PHY is seperated from usb controller.
>>>> The usb controller used in marvell pxa168/pxa910/mmp2 are same,
>>>> but PHY initialization may be different.
>>>> the usb controller can support udc/otg/ehci, and for each of
>>>> the mode, it need PHY to initialized before use the controller.
>>>> Direclty writing the phy driver will make the usb controller
>>>> driver to be simple and portable.
>>>> The PHY driver will be used by marvell udc/otg/ehci.
>>>>
>>>> Signed-off-by: Chao Xie <chao.xie at marvell.com>
>>>> ---
>>>> drivers/usb/phy/Kconfig | 7 +
>>>> drivers/usb/phy/Makefile | 1 +
>>>> drivers/usb/phy/mv_usb2_phy.c | 454
>>>> ++++++++++++++++++++++++++++++++++
>>>> include/linux/platform_data/mv_usb.h | 9 +-
>>>> include/linux/usb/mv_usb2.h | 43 ++++
>>>> 5 files changed, 511 insertions(+), 3 deletions(-)
>>>> create mode 100644 drivers/usb/phy/mv_usb2_phy.c
>>>> create mode 100644 include/linux/usb/mv_usb2.h
>>>>
>>>> diff --git a/drivers/usb/phy/Kconfig b/drivers/usb/phy/Kconfig
>>>> index 65217a5..5479760 100644
>>>> --- a/drivers/usb/phy/Kconfig
>>>> +++ b/drivers/usb/phy/Kconfig
>>>> @@ -73,3 +73,10 @@ config SAMSUNG_USBPHY
>>>> help
>>>> Enable this to support Samsung USB phy controller for samsung
>>>> SoCs.
>>>> +
>>>> +config MV_USB2_PHY
>>>> + tristate "Marvell USB 2.0 PHY Driver"
>>>> + depends on USB || USB_GADGET
>>>> + help
>>>> + Enable this to support Marvell USB 2.0 phy driver for Marvell
>>>> + SoC.
>>>> diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
>>>> index b13faa1..3835316 100644
>>>> --- a/drivers/usb/phy/Makefile
>>>> +++ b/drivers/usb/phy/Makefile
>>>> @@ -12,3 +12,4 @@ obj-$(CONFIG_MV_U3D_PHY) += mv_u3d_phy.o
>>>> obj-$(CONFIG_USB_EHCI_TEGRA) += tegra_usb_phy.o
>>>> obj-$(CONFIG_USB_RCAR_PHY) += rcar-phy.o
>>>> obj-$(CONFIG_SAMSUNG_USBPHY) += samsung-usbphy.o
>>>> +obj-$(CONFIG_MV_USB2_PHY) += mv_usb2_phy.o
>>>> diff --git a/drivers/usb/phy/mv_usb2_phy.c
>>>> b/drivers/usb/phy/mv_usb2_phy.c
>>>> new file mode 100644
>>>> index 0000000..c2bccae
>>>> --- /dev/null
>>>> +++ b/drivers/usb/phy/mv_usb2_phy.c
>>>> @@ -0,0 +1,454 @@
>>>> +/*
>>>> + * Copyright (C) 2010 Google, Inc.
>>>> + *
>>>> + * Author:
>>>> + * Chao Xie <xiechao.mail at gmail.com>
>>>> + *
>>>> + * This software is licensed under the terms of the GNU General Public
>>>> + * License version 2, as published by the Free Software Foundation, and
>>>> + * may be copied, distributed, and modified under those terms.
>>>> + *
>>>> + * This program is distributed in the hope that it will be useful,
>>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>>>> + * GNU General Public License for more details.
>>>> + *
>>>> + */
>>>> +
>>>> +#include <linux/resource.h>
>>>> +#include <linux/delay.h>
>>>> +#include <linux/slab.h>
>>>> +#include <linux/of.h>
>>>> +#include <linux/of_device.h>
>>>> +#include <linux/io.h>
>>>> +#include <linux/err.h>
>>>> +#include <linux/clk.h>
>>>> +#include <linux/export.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <linux/platform_data/mv_usb.h>
>>>> +#include <linux/usb/mv_usb2.h>
>>>> +
>>>> +/* phy regs */
>>>> +#define UTMI_REVISION 0x0
>>>> +#define UTMI_CTRL 0x4
>>>> +#define UTMI_PLL 0x8
>>>> +#define UTMI_TX 0xc
>>>> +#define UTMI_RX 0x10
>>>> +#define UTMI_IVREF 0x14
>>>> +#define UTMI_T0 0x18
>>>> +#define UTMI_T1 0x1c
>>>> +#define UTMI_T2 0x20
>>>> +#define UTMI_T3 0x24
>>>> +#define UTMI_T4 0x28
>>>> +#define UTMI_T5 0x2c
>>>> +#define UTMI_RESERVE 0x30
>>>> +#define UTMI_USB_INT 0x34
>>>> +#define UTMI_DBG_CTL 0x38
>>>> +#define UTMI_OTG_ADDON 0x3c
>>>> +
>>>> +/* For UTMICTRL Register */
>>>> +#define UTMI_CTRL_USB_CLK_EN (1 << 31)
>>>> +/* pxa168 */
>>>> +#define UTMI_CTRL_SUSPEND_SET1 (1 << 30)
>>>> +#define UTMI_CTRL_SUSPEND_SET2 (1 << 29)
>>>> +#define UTMI_CTRL_RXBUF_PDWN (1 << 24)
>>>> +#define UTMI_CTRL_TXBUF_PDWN (1 << 11)
>>>> +
>>>> +#define UTMI_CTRL_INPKT_DELAY_SHIFT 30
>>>> +#define UTMI_CTRL_INPKT_DELAY_SOF_SHIFT 28
>>>> +#define UTMI_CTRL_PU_REF_SHIFT 20
>>>> +#define UTMI_CTRL_ARC_PULLDN_SHIFT 12
>>>> +#define UTMI_CTRL_PLL_PWR_UP_SHIFT 1
>>>> +#define UTMI_CTRL_PWR_UP_SHIFT 0
>>>> +
>>>> +/* For UTMI_PLL Register */
>>>> +#define UTMI_PLL_PLLCALI12_SHIFT 29
>>>> +#define UTMI_PLL_PLLCALI12_MASK (0x3 << 29)
>>>> +
>>>> +#define UTMI_PLL_PLLVDD18_SHIFT 27
>>>> +#define UTMI_PLL_PLLVDD18_MASK (0x3 << 27)
>>>> +
>>>> +#define UTMI_PLL_PLLVDD12_SHIFT 25
>>>> +#define UTMI_PLL_PLLVDD12_MASK (0x3 << 25)
>>>> +
>>>> +#define UTMI_PLL_CLK_BLK_EN_SHIFT 24
>>>> +#define CLK_BLK_EN (0x1 << 24)
>>>> +#define PLL_READY (0x1 << 23)
>>>> +#define KVCO_EXT (0x1 << 22)
>>>> +#define VCOCAL_START (0x1 << 21)
>>>> +
>>>> +#define UTMI_PLL_KVCO_SHIFT 15
>>>> +#define UTMI_PLL_KVCO_MASK (0x7 << 15)
>>>> +
>>>> +#define UTMI_PLL_ICP_SHIFT 12
>>>> +#define UTMI_PLL_ICP_MASK (0x7 << 12)
>>>> +
>>>> +#define UTMI_PLL_FBDIV_SHIFT 4
>>>> +#define UTMI_PLL_FBDIV_MASK (0xFF << 4)
>>>> +
>>>> +#define UTMI_PLL_REFDIV_SHIFT 0
>>>> +#define UTMI_PLL_REFDIV_MASK (0xF << 0)
>>>> +
>>>> +/* For UTMI_TX Register */
>>>> +#define UTMI_TX_REG_EXT_FS_RCAL_SHIFT 27
>>>> +#define UTMI_TX_REG_EXT_FS_RCAL_MASK (0xf << 27)
>>>> +
>>>> +#define UTMI_TX_REG_EXT_FS_RCAL_EN_SHIFT 26
>>>> +#define UTMI_TX_REG_EXT_FS_RCAL_EN_MASK (0x1 << 26)
>>>> +
>>>> +#define UTMI_TX_TXVDD12_SHIFT 22
>>>> +#define UTMI_TX_TXVDD12_MASK (0x3 << 22)
>>>> +
>>>> +#define UTMI_TX_CK60_PHSEL_SHIFT 17
>>>> +#define UTMI_TX_CK60_PHSEL_MASK (0xf << 17)
>>>> +
>>>> +#define UTMI_TX_IMPCAL_VTH_SHIFT 14
>>>> +#define UTMI_TX_IMPCAL_VTH_MASK (0x7 << 14)
>>>> +
>>>> +#define REG_RCAL_START (0x1 << 12)
>>>> +
>>>> +#define UTMI_TX_LOW_VDD_EN_SHIFT 11
>>>> +
>>>> +#define UTMI_TX_AMP_SHIFT 0
>>>> +#define UTMI_TX_AMP_MASK (0x7 << 0)
>>>> +
>>>> +/* For UTMI_RX Register */
>>>> +#define UTMI_REG_SQ_LENGTH_SHIFT 15
>>>> +#define UTMI_REG_SQ_LENGTH_MASK (0x3 << 15)
>>>> +
>>>> +#define UTMI_RX_SQ_THRESH_SHIFT 4
>>>> +#define UTMI_RX_SQ_THRESH_MASK (0xf << 4)
>>>> +
>>>> +#define UTMI_OTG_ADDON_OTG_ON (1 << 0)
>>>> +
>>>> +enum mv_usb2_phy_type {
>>>> + PXA168_USB,
>>>> + PXA910_USB,
>>>> + MMP2_USB,
>>>> +};
>>>> +
>>>> +static struct mv_usb2_phy *the_phy;
>>>> +
>>>> +struct mv_usb2_phy *mv_usb2_get_phy(void)
>>>> +{
>>>> + return the_phy;
>>>> +}
>>>> +EXPORT_SYMBOL(mv_usb2_get_phy);
>>>> +
>>>> +static unsigned int u2o_get(void __iomem *base, unsigned int offset)
>>>> +{
>>>> + return readl(base + offset);
>>>> +}
>>>> +
>>>> +static void u2o_set(void __iomem *base, unsigned int offset,
>>>> + unsigned int value)
>>>> +{
>>>> + u32 reg;
>>>> +
>>>> + reg = readl(base + offset);
>>>> + reg |= value;
>>>> + writel(reg, base + offset);
>>>> + readl(base + offset);
>>>> +}
>>>> +
>>>> +static void u2o_clear(void __iomem *base, unsigned int offset,
>>>> + unsigned int value)
>>>> +{
>>>> + u32 reg;
>>>> +
>>>> + reg = readl(base + offset);
>>>> + reg &= ~value;
>>>> + writel(reg, base + offset);
>>>> + readl(base + offset);
>>>> +}
>>>> +
>>>> +static void u2o_write(void __iomem *base, unsigned int offset,
>>>> + unsigned int value)
>>>> +{
>>>> + writel(value, base + offset);
>>>> + readl(base + offset);
>>>> +}
>>>> +
>>>> +static int _usb_phy_init(struct mv_usb2_phy *mv_phy)
>>>> +{
>>>> + struct platform_device *pdev = mv_phy->pdev;
>>>> + unsigned int loops = 0;
>>>> + void __iomem *base = mv_phy->base;
>>>> +
>>>> + dev_dbg(&pdev->dev, "phy init\n");
>>>> +
>>>> + /* Initialize the USB PHY power */
>>>> + if (mv_phy->type == PXA910_USB) {
>>>> + u2o_set(base, UTMI_CTRL,
>>>> (1<<UTMI_CTRL_INPKT_DELAY_SOF_SHIFT)
>>>> + | (1<<UTMI_CTRL_PU_REF_SHIFT));
>>>> + }
>>>> +
>>>> + u2o_set(base, UTMI_CTRL, 1<<UTMI_CTRL_PLL_PWR_UP_SHIFT);
>>>> + u2o_set(base, UTMI_CTRL, 1<<UTMI_CTRL_PWR_UP_SHIFT);
>>>> +
>>>> + /* UTMI_PLL settings */
>>>> + u2o_clear(base, UTMI_PLL, UTMI_PLL_PLLVDD18_MASK
>>>> + | UTMI_PLL_PLLVDD12_MASK | UTMI_PLL_PLLCALI12_MASK
>>>> + | UTMI_PLL_FBDIV_MASK | UTMI_PLL_REFDIV_MASK
>>>> + | UTMI_PLL_ICP_MASK | UTMI_PLL_KVCO_MASK);
>>>> +
>>>> + u2o_set(base, UTMI_PLL, 0xee<<UTMI_PLL_FBDIV_SHIFT
>>>> + | 0xb<<UTMI_PLL_REFDIV_SHIFT |
>>>> 3<<UTMI_PLL_PLLVDD18_SHIFT
>>>> + | 3<<UTMI_PLL_PLLVDD12_SHIFT |
>>>> 3<<UTMI_PLL_PLLCALI12_SHIFT
>>>> + | 1<<UTMI_PLL_ICP_SHIFT | 3<<UTMI_PLL_KVCO_SHIFT);
>>>> +
>>>> + /* UTMI_TX */
>>>> + u2o_clear(base, UTMI_TX, UTMI_TX_REG_EXT_FS_RCAL_EN_MASK
>>>> + | UTMI_TX_TXVDD12_MASK | UTMI_TX_CK60_PHSEL_MASK
>>>> + | UTMI_TX_IMPCAL_VTH_MASK | UTMI_TX_REG_EXT_FS_RCAL_MASK
>>>> + | UTMI_TX_AMP_MASK);
>>>> + u2o_set(base, UTMI_TX, 3<<UTMI_TX_TXVDD12_SHIFT
>>>> + | 4<<UTMI_TX_CK60_PHSEL_SHIFT |
>>>> 4<<UTMI_TX_IMPCAL_VTH_SHIFT
>>>> + | 8<<UTMI_TX_REG_EXT_FS_RCAL_SHIFT |
>>>> 3<<UTMI_TX_AMP_SHIFT);
>>>> +
>>>> + /* UTMI_RX */
>>>> + u2o_clear(base, UTMI_RX, UTMI_RX_SQ_THRESH_MASK
>>>> + | UTMI_REG_SQ_LENGTH_MASK);
>>>> + u2o_set(base, UTMI_RX, 7<<UTMI_RX_SQ_THRESH_SHIFT
>>>> + | 2<<UTMI_REG_SQ_LENGTH_SHIFT);
>>>> +
>>>> + /* UTMI_IVREF */
>>>> + if (mv_phy->type == PXA168_USB)
>>>> + /* fixing Microsoft Altair board interface with NEC hub
>>>> issue -
>>>> + * Set UTMI_IVREF from 0x4a3 to 0x4bf */
>>>> + u2o_write(base, UTMI_IVREF, 0x4bf);
>>>> +
>>>> + /* toggle VCOCAL_START bit of UTMI_PLL */
>>>> + udelay(200);
>>>> + u2o_set(base, UTMI_PLL, VCOCAL_START);
>>>> + udelay(40);
>>>> + u2o_clear(base, UTMI_PLL, VCOCAL_START);
>>>> +
>>>> + /* toggle REG_RCAL_START bit of UTMI_TX */
>>>> + udelay(400);
>>>> + u2o_set(base, UTMI_TX, REG_RCAL_START);
>>>> + udelay(40);
>>>> + u2o_clear(base, UTMI_TX, REG_RCAL_START);
>>>> + udelay(400);
>>>> +
>>>> + /* Make sure PHY PLL is ready */
>>>> + loops = 0;
>>>> + while ((u2o_get(base, UTMI_PLL) & PLL_READY) == 0) {
>>>> + mdelay(1);
>>>> + loops++;
>>>> + if (loops > 100) {
>>>> + dev_warn(&pdev->dev, "calibrate timeout,
>>>> UTMI_PLL
>>>> %x\n",
>>>> + u2o_get(base, UTMI_PLL));
>>>> + break;
>>>> + }
>>>> + }
>>>> +
>>>> + if (mv_phy->type == PXA168_USB) {
>>>> + u2o_set(base, UTMI_RESERVE, 1 << 5);
>>>> + /* Turn on UTMI PHY OTG extension */
>>>> + u2o_write(base, UTMI_OTG_ADDON, 1);
>>>> + }
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int _usb_phy_shutdown(struct mv_usb2_phy *mv_phy)
>>>> +{
>>>> + void __iomem *base = mv_phy->base;
>>>> +
>>>> + if (mv_phy->type == PXA168_USB)
>>>> + u2o_clear(base, UTMI_OTG_ADDON, UTMI_OTG_ADDON_OTG_ON);
>>>> +
>>>> + u2o_clear(base, UTMI_CTRL, UTMI_CTRL_RXBUF_PDWN);
>>>> + u2o_clear(base, UTMI_CTRL, UTMI_CTRL_TXBUF_PDWN);
>>>> + u2o_clear(base, UTMI_CTRL, UTMI_CTRL_USB_CLK_EN);
>>>> + u2o_clear(base, UTMI_CTRL, 1<<UTMI_CTRL_PWR_UP_SHIFT);
>>>> + u2o_clear(base, UTMI_CTRL, 1<<UTMI_CTRL_PLL_PWR_UP_SHIFT);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int usb_phy_init(struct mv_usb2_phy *mv_phy)
>>>> +{
>>>> + int i = 0;
>>>> +
>>>> + mutex_lock(&mv_phy->phy_lock);
>>>> + if (mv_phy->refcount++ == 0) {
>>>> + for (i = 0; i < mv_phy->clks_num; i++)
>>>> + clk_prepare_enable(mv_phy->clks[i]);
>>>> + _usb_phy_init(mv_phy);
>>>> + }
>>>> + mutex_unlock(&mv_phy->phy_lock);
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static void usb_phy_shutdown(struct mv_usb2_phy *mv_phy)
>>>> +{
>>>> + int i = 0;
>>>> +
>>>> + mutex_lock(&mv_phy->phy_lock);
>>>> + if (mv_phy->refcount++ == 0) {
>>>> + _usb_phy_shutdown(mv_phy);
>>>> + for (i = 0; i < mv_phy->clks_num; i++)
>>>> + clk_disable_unprepare(mv_phy->clks[i]);
>>>> + }
>>>> + mutex_unlock(&mv_phy->phy_lock);
>>>> +}
>>>> +
>>>> +static struct of_device_id usb_phy_dt_ids[] = {
>>>> + { .compatible = "mrvl,pxa168-usb-phy", .data = (void
>>>> *)PXA168_USB},
>>>> + { .compatible = "mrvl,pxa910-usb-phy", .data = (void
>>>> *)PXA910_USB},
>>>> + { .compatible = "mrvl,mmp2-usb-phy", .data = (void
>>>> *)MMP2_USB},
>>>> + {}
>>>> +};
>>>> +MODULE_DEVICE_TABLE(of, usb_phy_dt_ids);
>>>> +
>>>> +static int usb_phy_parse_dt(struct platform_device *pdev,
>>>> + struct mv_usb2_phy *mv_phy)
>>>> +{
>>>> + struct device_node *np = pdev->dev.of_node;
>>>> + const struct of_device_id *of_id =
>>>> + of_match_device(usb_phy_dt_ids, &pdev->dev);
>>>> + unsigned int clks_num;
>>>> + int i, ret;
>>>> + const char *clk_name;
>>>> +
>>>> + if (!np)
>>>> + return 1;
>>>> +
>>>> + clks_num = of_property_count_strings(np, "clocks");
>>>> + if (clks_num < 0) {
>>>> + dev_err(&pdev->dev, "failed to get clock number\n");
>>>> + return clks_num;
>>>> + }
>>>> +
>>>> + mv_phy->clks = devm_kzalloc(&pdev->dev,
>>>> + sizeof(struct clk *) * clks_num, GFP_KERNEL);
>>>> + if (mv_phy->clks == NULL) {
>>>> + dev_err(&pdev->dev,
>>>> + "failed to allocate mempory for clocks");
>>>> + return -ENOMEM;
>>>> + }
>>>> +
>>>> + for (i = 0; i < clks_num; i++) {
>>>> + ret = of_property_read_string_index(np, "clocks", i,
>>>> + &clk_name);
>>>> + if (ret) {
>>>> + dev_err(&pdev->dev, "failed to read clocks\n");
>>>> + return ret;
>>>> + }
>>>> + mv_phy->clks[i] = devm_clk_get(&pdev->dev, clk_name);
>>>> + if (IS_ERR(mv_phy->clks[i])) {
>>>> + dev_err(&pdev->dev, "failed to get clock %s\n",
>>>> + clk_name);
>>>> + return PTR_ERR(mv_phy->clks[i]);
>>>> + }
>>>> + }
>>>> +
>>>> + mv_phy->clks_num = clks_num;
>>>> + mv_phy->type = (enum mv_usb2_phy_type)(of_id->data);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int usb_phy_probe(struct platform_device *pdev)
>>>> +{
>>>> + struct mv_usb2_phy *mv_phy;
>>>> + struct resource *r;
>>>> + int ret, i;
>>>> +
>>>> + mv_phy = devm_kzalloc(&pdev->dev, sizeof(*mv_phy), GFP_KERNEL);
>>>> + if (mv_phy == NULL) {
>>>> + dev_err(&pdev->dev, "failed to allocate memory\n");
>>>> + return -ENOMEM;
>>>> + }
>>>> + mutex_init(&mv_phy->phy_lock);
>>>> +
>>>> + ret = usb_phy_parse_dt(pdev, mv_phy);
>>>> + /* no CONFIG_OF */
>>>> + if (ret > 0) {
>>>> + struct mv_usb_phy_platform_data *pdata
>>>> + = pdev->dev.platform_data;
>>>> + const struct platform_device_id *id
>>>> + = platform_get_device_id(pdev);
>>>> +
>>>> + if (pdata == NULL || id == NULL) {
>>>> + dev_err(&pdev->dev,
>>>> + "missing platform_data or id_entry\n");
>>>> + return -ENODEV;
>>>> + }
>>>> + mv_phy->type = (unsigned int)(id->driver_data);
>>>> + mv_phy->clks_num = pdata->clknum;
>>>> + mv_phy->clks = devm_kzalloc(&pdev->dev,
>>>> + sizeof(struct clk *) * mv_phy->clks_num,
>>>> GFP_KERNEL);
>>>> + if (mv_phy->clks == NULL) {
>>>> + dev_err(&pdev->dev,
>>>> + "failed to allocate mempory for
>>>> clocks");
>>>> + return -ENOMEM;
>>>> + }
>>>> + for (i = 0; i < mv_phy->clks_num; i++)
>>>> + mv_phy->clks[i] = devm_clk_get(&pdev->dev,
>>>> +
>>>> pdata->clkname[i]);
>>>> + if (IS_ERR(mv_phy->clks[i])) {
>>>> + dev_err(&pdev->dev, "failed to get clock
>>>> %s\n",
>>>> + pdata->clkname[i]);
>>>> + return PTR_ERR(mv_phy->clks[i]);
>>>> + }
>>>> + } else if (ret < 0) {
>>>> + dev_err(&pdev->dev, "error parse dt\n");
>>>> + return ret;
>>>> + }
>>>> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>>> + if (r == NULL) {
>>>> + dev_err(&pdev->dev, "no phy I/O memory resource
>>>> defined\n");
>>>> + return -ENODEV;
>>>> + }
>>>> + mv_phy->base = devm_ioremap(&pdev->dev, r->start,
>>>> resource_size(r));
>>>> + if (mv_phy->base == NULL) {
>>>> + dev_err(&pdev->dev, "error map register base\n");
>>>> + return -EBUSY;
>>>> + }
>>>> + platform_set_drvdata(pdev, mv_phy);
>>>> + mv_phy->pdev = pdev;
>>>> + mv_phy->init = usb_phy_init;
>>>> + mv_phy->shutdown = usb_phy_shutdown;
>>>> +
>>>> + platform_set_drvdata(pdev, mv_phy);
>>>> +
>>>> + the_phy = mv_phy;
>>>
>>>
>>>
>>> Is there any specific reason for not using the usb phy library?
>>> Please use the APIs provided in drivers/usb/otg/otg.c.
>>> These APIs will be moved to phy.c soon.
>>>
>>> Thanks
>>> Kishon
>>
>>
>> The phy in driver/usb/otg/otg.c is bound to OTG. The major target of
>> this APIs in OTG is help functions for OTG support.
>
>
> Not really. Much of what's in otg.c is related to PHY and we have an action
> item to rename otg.c to phy.c. Sascha hauer has already sent a patch for it.
>
>> I have used it and implemented it at mv_otg.c for OTG support. The
>> APIs only allow one phy driver register to it.
>
>
> PHY library has changed quite a bit since then. You might want to have a
> look at usb/otg/otg.c again in usb-next.
>
Thanks for your suggestion.
I have taken look at the otg.c again.
The problem is the phy list only allow a single phy driver for each type.
It defines only two valid types
USB_PHY_TYPE_USB2,
USB_PHY_TYPE_USB3,
when invoke usb_add_phy to add a phy driver, if USB_PHY_TYPE_USB2 has
been added, it will return error
some piece of the code is listed below
list_for_each_entry(phy, &phy_list, head) {
if (phy->type == type) {
ret = -EBUSY;
dev_err(x->dev, "transceiver type %s already exists\n",
usb_phy_type_string(type));
goto out;
}
}
The USB IP we used includes EHCI and UDC controller together, and it
can support OTG functions.
When either mode(EHCI/UDC) is used, the PHY blocks should be enabled
because it controller to turn
the internal signals of USB IP block to the D+/D-/VBUS signals we see.
So if we register this phy to be type USB_PHY_TYPE_USB2, then how about OTG?
For OTG support we need register the PHY to complete the device->host
and host->device transaction, if we register it as
USB_PHY_TYPE_USB2, the registertation will fail.
So there will be three ways to do the job
way1:
1. invoke usb_add_phy in phy driver with type of USB_PHY_TYPE_USB2,
and initialize the callbacks
2. in usb otg driver, invoke usb_get_phy and initialize the otg part
way1 seems a little tricky because when the phy initialize is
seperated into two parts.
way2:
change the otg.c and make it can add mutiple phy for the type.
It takes time and will impact many drivers. I hope i can do it after i
have completed my patches.
way3:
It is what i have done in the patch series.
> Thanks
> Kishon
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