| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <DB5PR0401MB1928CA058CC01243457F124791BC0@DB5PR0401MB1928.eurprd04.prod.outlook.com>
Date: Mon, 14 Nov 2016 16:07:55 +0000
From: Scott Wood <scott.wood@....com>
To: Sriram Dash <sriram.dash@....com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>,
"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>
CC: "mark.rutland@....com" <mark.rutland@....com>,
"felipe.balbi@...ux.intel.com" <felipe.balbi@...ux.intel.com>,
"mathias.nyman@...el.com" <mathias.nyman@...el.com>,
"catalin.marinas@....com" <catalin.marinas@....com>,
"will.deacon@....com" <will.deacon@....com>,
"kishon@...com" <kishon@...com>,
"robh+dt@...nel.org" <robh+dt@...nel.org>,
"stern@...land.harvard.edu" <stern@...land.harvard.edu>,
Suresh Gupta <suresh.gupta@....com>,
"gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
"pku.leo@...il.com" <pku.leo@...il.com>
Subject: Re: [upstream-release] [PATCH 1/2] drivers: usb: phy: Add qoriq usb
3.0 phy driver support
On 11/13/2016 11:27 PM, Sriram Dash wrote:
> diff --git a/Documentation/devicetree/bindings/phy/phy-qoriq-usb3.txt b/Documentation/devicetree/bindings/phy/phy-qoriq-usb3.txt
> new file mode 100644
> index 0000000..d934c80
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/phy-qoriq-usb3.txt
> @@ -0,0 +1,36 @@
> +Driver for Freescale USB 3.0 PHY
> +
> +Required properties:
> +
> +- compatible : fsl,qoriq-usb3-phy
This is a very vague compatible. Are there versioning registers within
this register block?
> +/* Parameter control */
> +#define USB3PRM1CR 0x000
> +#define USB3PRM1CR_VAL 0x27672b2a
> +
> +/*
> + * struct qoriq_usb3_phy - driver data for USB 3.0 PHY
> + * @dev: pointer to device instance of this platform device
> + * @param_ctrl: usb3 phy parameter control register base
> + * @phy_base: usb3 phy register memory base
> + * @has_erratum_flag: keeps track of erratum applicable on device
> + */
> +struct qoriq_usb3_phy {
> + struct device *dev;
> + void __iomem *param_ctrl;
> + void __iomem *phy_base;
> + u32 has_erratum_flag;
> +};
> +
> +static inline u32 qoriq_usb3_phy_readl(void __iomem *addr, u32 offset)
> +{
> + return __raw_readl(addr + offset);
> +}
> +
> +static inline void qoriq_usb3_phy_writel(void __iomem *addr, u32 offset,
> + u32 data)
> +{
> + __raw_writel(data, addr + offset);
> +}
Why raw? Besides missing barriers, this will cause the accesses to be
native-endian which is not correct.
> +/*
> + * Erratum A008751
> + * SCFG USB3PRM1CR has incorrect default value
> + * SCFG USB3PRM1CR reset value should be 32'h27672B2A instead of 32'h25E72B2A.
When documenting C code, can you stick with C-style numeric constants?
For that matter, just put the constant in the code instead of hiding it
in an overly-generically-named USB3PRM1CR_VAL and then you won't need to
redundantly state the value in a comment. Normally putting magic
numbers in symbolic constants is a good thing, but in this case it's not
actually describing anything and the number is of no meaning outside of
this one erratum workaround (it might even be a different value if
another chip has a similar erratum).
> + */
> +static void erratum_a008751(struct qoriq_usb3_phy *phy)
> +{
> + qoriq_usb3_phy_writel(phy->param_ctrl, USB3PRM1CR,
> + USB3PRM1CR_VAL);
> +}
> +
> +/*
> + * qoriq_usb3_phy_erratum - List of phy erratum
> + * @qoriq_phy_erratum - erratum application
> + * @compat - comapt string for erratum
> + */
> +
> +struct qoriq_usb3_phy_erratum {
> + void (*qoriq_phy_erratum)(struct qoriq_usb3_phy *phy);
> + char *compat;
> +};
> +
> +/* Erratum list */
> +struct qoriq_usb3_phy_erratum phy_erratum_tbl[] = {
> + {&erratum_a008751, "fsl,usb-erratum-a008751"},
> + /* Add init time erratum here */
> +};
This needs to be static.
Unnecessary & on the function pointer.
> +static int qoriq_usb3_phy_init(struct phy *x)
> +{
> + struct qoriq_usb3_phy *phy = phy_get_drvdata(x);
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(phy_erratum_tbl); i++)
> + if (phy->has_erratum_flag & 1 << i)
> + phy_erratum_tbl[i].qoriq_phy_erratum(phy);
> + return 0;
> +}
> +
> +static const struct phy_ops ops = {
> + .init = qoriq_usb3_phy_init,
> + .owner = THIS_MODULE,
> +};
> +
> +static int qoriq_usb3_phy_probe(struct platform_device *pdev)
> +{
> + struct qoriq_usb3_phy *phy;
> + struct phy *generic_phy;
> + struct phy_provider *phy_provider;
> + const struct of_device_id *of_id;
> + struct device *dev = &pdev->dev;
> + struct resource *res;
> + int i, ret;
> +
> + phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
> + if (!phy)
> + return -ENOMEM;
> + phy->dev = dev;
> +
> + of_id = of_match_device(dev->driver->of_match_table, dev);
> + if (!of_id) {
> + dev_err(dev, "failed to get device match\n");
> + ret = -EINVAL;
> + goto err_out;
> + }
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "param_ctrl");
> + if (!res) {
> + dev_err(dev, "failed to get param_ctrl memory\n");
> + ret = -ENOENT;
> + goto err_out;
> + }
> +
> + phy->param_ctrl = devm_ioremap_resource(dev, res);
> + if (!phy->param_ctrl) {
> + dev_err(dev, "failed to remap param_ctrl memory\n");
> + ret = -ENOMEM;
> + goto err_out;
> + }
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy_base");
> + if (!res) {
> + dev_err(dev, "failed to get phy_base memory\n");
> + ret = -ENOENT;
> + goto err_out;
> + }
> +
> + phy->phy_base = devm_ioremap_resource(dev, res);
> + if (!phy->phy_base) {
> + dev_err(dev, "failed to remap phy_base memory\n");
> + ret = -ENOMEM;
> + goto err_out;
> + }
> +
> + phy->has_erratum_flag = 0;
> + for (i = 0; i < ARRAY_SIZE(phy_erratum_tbl); i++)
> + phy->has_erratum_flag |= device_property_read_bool(dev,
> + phy_erratum_tbl[i].compat) << i;
I don't see the erratum property in either the binding or the device
tree. Also, a property name is not a "compat".
Is there a reason why this flag and array mechanism is needed, rather
than just checking the erratum properties from the init function -- or,
if you have a good reason to not want to do device tree accesses from
init, just using a bool per erratum? How many errata are you expecting?
-Scott
Powered by blists - more mailing lists