Re: [PATCH v4 2/4] phy: qcom-qusb2: New driver for QUSB2 PHY on Qcom chips
From: Vivek Gautam
Date: Wed Jan 18 2017 - 04:13:31 EST
Hi Kishon,
On 01/16/2017 02:15 PM, Kishon Vijay Abraham I wrote:
Hi,
On Tuesday 10 January 2017 04:21 PM, Vivek Gautam wrote:
PHY transceiver driver for QUSB2 phy controller that provides
HighSpeed functionality for DWC3 controller present on
Qualcomm chipsets.
Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
---
Changes since v3:
- Added 'Reviewed-by' from Stephen.
- Fixed debug message for qusb2_phy_set_tune2_param().
- Replaced devm_reset_control_get() with devm_reset_control_get_by_index()
since we are requesting only one reset.
- Updated devm_nvmem_cell_get() with a NULL cell id.
- Made error labels more idiomatic.
- Refactored qusb2_setbits() and qusb2_clrbits() a little bit to accept
base address and register offset as two separate arguments.
Changes since v2:
- Removed selecting 'RESET_CONTROLLER' config.
- Added error handling for clk_prepare_enable paths.
- Removed explicitly setting ref_clk rate to 19.2 MHz. Don't need to
do that since 'xo' is modeled as parent to this clock.
- Removed 'ref_clk_src' handling. Driver doesn't need to request and
handle this clock.
- Moved nvmem_cell_get() to probe function.
- Simplified phy pll status handling.
- Using of_device_get_match_data() to get match data.
- Uniformly using lowercase for hex numbers.
- Fixed sparse warnings.
- Using shorter variable names in structure and in functions.
- Handling various comment style shortcomings.
Changes since v1:
- removed reference to clk_enabled/pwr_enabled.
- moved clock and regulator enable code to phy_power_on/off() callbacks.
- fixed return on EPROBE_DEFER in qusb2_phy_probe().
- fixed phy create and phy register ordering.
- removed references to non-lkml links from commit message.
- took care of other minor nits.
- Fixed coccinelle warnings -
'PTR_ERR applied after initialization to constant'
- Addressed review comment, regarding qfprom access for tune2 param value.
This driver is now based on qfprom patch[1] that allows byte access now.
drivers/phy/Kconfig | 10 +
drivers/phy/Makefile | 1 +
drivers/phy/phy-qcom-qusb2.c | 539 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 550 insertions(+)
create mode 100644 drivers/phy/phy-qcom-qusb2.c
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index e8eb7f225a88..0ed53d018b23 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -430,6 +430,16 @@ config PHY_STIH407_USB
Enable this support to enable the picoPHY device used by USB2
and USB3 controllers on STMicroelectronics STiH407 SoC families.
+config PHY_QCOM_QUSB2
+ tristate "Qualcomm QUSB2 PHY Driver"
+ depends on OF && (ARCH_QCOM || COMPILE_TEST)
+ select GENERIC_PHY
+ help
+ Enable this to support the HighSpeed QUSB2 PHY transceiver for USB
+ controllers on Qualcomm chips. This driver supports the high-speed
+ PHY which is usually paired with either the ChipIdea or Synopsys DWC3
+ USB IPs on MSM SOCs.
+
config PHY_QCOM_UFS
tristate "Qualcomm UFS PHY driver"
depends on OF && ARCH_QCOM
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 65eb2f436a41..dad1682b80e3 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY) += phy-spear1310-miphy.o
obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY) += phy-spear1340-miphy.o
obj-$(CONFIG_PHY_XGENE) += phy-xgene.o
obj-$(CONFIG_PHY_STIH407_USB) += phy-stih407-usb.o
+obj-$(CONFIG_PHY_QCOM_QUSB2) += phy-qcom-qusb2.o
obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs.o
obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs-qmp-20nm.o
obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs-qmp-14nm.o
diff --git a/drivers/phy/phy-qcom-qusb2.c b/drivers/phy/phy-qcom-qusb2.c
new file mode 100644
index 000000000000..c69118610164
--- /dev/null
+++ b/drivers/phy/phy-qcom-qusb2.c
@@ -0,0 +1,539 @@
+/*
+ * Copyright (c) 2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+
+#define QUSB2PHY_PLL_TEST 0x04
+#define CLK_REF_SEL BIT(7)
+
+#define QUSB2PHY_PLL_TUNE 0x08
+#define QUSB2PHY_PLL_USER_CTL1 0x0c
+#define QUSB2PHY_PLL_USER_CTL2 0x10
+#define QUSB2PHY_PLL_AUTOPGM_CTL1 0x1c
+#define QUSB2PHY_PLL_PWR_CTRL 0x18
+
+#define QUSB2PHY_PLL_STATUS 0x38
+#define PLL_LOCKED BIT(5)
+
+#define QUSB2PHY_PORT_TUNE1 0x80
+#define QUSB2PHY_PORT_TUNE2 0x84
+#define QUSB2PHY_PORT_TUNE3 0x88
+#define QUSB2PHY_PORT_TUNE4 0x8c
+#define QUSB2PHY_PORT_TUNE5 0x90
+#define QUSB2PHY_PORT_TEST2 0x9c
+
+#define QUSB2PHY_PORT_POWERDOWN 0xb4
+#define CLAMP_N_EN BIT(5)
+#define FREEZIO_N BIT(1)
+#define POWER_DOWN BIT(0)
+
+#define QUSB2PHY_REFCLK_ENABLE BIT(0)
+
+#define PHY_CLK_SCHEME_SEL BIT(0)
+
+struct qusb2_phy_init_tbl {
+ unsigned int offset;
+ unsigned int val;
+};
+#define QUSB2_PHY_INIT_CFG(o, v) \
+ { \
+ .offset = o, \
+ .val = v, \
+ }
+
+static const struct qusb2_phy_init_tbl msm8996_init_tbl[] = {
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PORT_TUNE1, 0xf8),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PORT_TUNE2, 0xb3),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PORT_TUNE3, 0x83),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PORT_TUNE4, 0xc0),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PLL_TUNE, 0x30),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PLL_USER_CTL1, 0x79),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PLL_USER_CTL2, 0x21),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PORT_TEST2, 0x14),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PLL_AUTOPGM_CTL1, 0x9f),
+ QUSB2_PHY_INIT_CFG(QUSB2PHY_PLL_PWR_CTRL, 0x00),
+};
I wish all this data comes from device tree and one API in phy-core can do all
these settings. Your other driver qcom-qmp also seems to have a bunch of
similar settings.
The problem is every vendor driver adds a bunch of code to perform the same
thing again and again when all of these settings can be done by a single phy API.
Yes, i understand this. You have commented similar thing in the patch
from Jaehoon -
[PATCH V2 2/5] phy: phy-exynos-pcie: Add support for Exynos PCIe phy
I would like to understand the requirements here.
Would you like me to get all this information from the device tree -
an array of register offset and value pair, which we can then program
by calling a phy_ops (may be calibrate) ? Something of this sort:
phy-calibrate-data = <val1, register_offset1>,
<val2, register_offset2>,
<val3, register_offset3>,
....
I am sure having such information in the driver (like i have in my patch)
makes the driver look more clumsy.
But, all this data can be pretty huge - a set of some 100+
register-value pairs
for QMP phy, for example. So, will it be okay to get this from device tree ?
We also note here that such information changes from one IP version to
another.
I remember Rob having some concerns about it.
Regards
Vivek
Thanks
Kishon
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