From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philipp Zabel Subject: Re: [PATCH 2/2] usb; dwc3: of-simple: Add support to get resets for the device Date: Wed, 15 Mar 2017 11:45:27 +0100 Message-ID: <1489574727.2528.13.camel@pengutronix.de> References: <1487741048-24659-1-git-send-email-vivek.gautam@codeaurora.org> <1487741048-24659-2-git-send-email-vivek.gautam@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1487741048-24659-2-git-send-email-vivek.gautam-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vivek Gautam Cc: balbi-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org On Wed, 2017-02-22 at 10:54 +0530, Vivek Gautam wrote: > Add support to get a list of resets available for the device. > These resets must be kept de-asserted until the device is > in use. > > Cc: Felipe Balbi > Signed-off-by: Vivek Gautam > --- > > Based on torvald's master branch. > > drivers/usb/dwc3/dwc3-of-simple.c | 49 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 49 insertions(+) > > diff --git a/drivers/usb/dwc3/dwc3-of-simple.c b/drivers/usb/dwc3/dwc3-of-simple.c > index fe414e7a9c78..025de7342d28 100644 > --- a/drivers/usb/dwc3/dwc3-of-simple.c > +++ b/drivers/usb/dwc3/dwc3-of-simple.c > @@ -29,13 +29,52 @@ > #include > #include > #include > +#include > > struct dwc3_of_simple { > struct device *dev; > struct clk **clks; > int num_clocks; > + struct reset_control **resets; > + int num_resets; > }; > > +static int dwc3_of_simple_reset_init(struct dwc3_of_simple *simple, int count) > +{ > + struct device *dev = simple->dev; > + int i; > + > + simple->num_resets = count; > + > + if (!count) > + return 0; > + > + simple->resets = devm_kcalloc(dev, simple->num_resets, > + sizeof(struct reset_control *), GFP_KERNEL); > + if (!simple->resets) > + return -ENOMEM; > + > + for (i = 0; i < simple->num_resets; i++) { > + struct reset_control *reset; > + int ret; > + > + reset = devm_reset_control_get_by_index(dev, i); Please use devm_reset_control_get_exclusive_by_index instead. See include/linux/reset.h for details. > + if (IS_ERR(reset)) > + return PTR_ERR(reset); > + > + simple->resets[i] = reset; > + > + ret = reset_control_deassert(reset); > + if (ret) { > + while (--i >= 0) > + reset_control_assert(reset); > + return ret; > + } > + } > + > + return 0; > +} This looks rather generic. Should we have a reset_control_get/assert/deassert_array functionality at the reset API level? > static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count) > { > struct device *dev = simple->dev; > @@ -100,6 +139,10 @@ static int dwc3_of_simple_probe(struct platform_device *pdev) > if (ret) > return ret; > > + ret = dwc3_of_simple_reset_init(simple, of_reset_control_get_count(np)); > + if (ret) > + return ret; > + Not a blocker, but it seems a bit inconsistent to count the reset controls via the device node (of_...), but then get them via the device (devm_reset_control_get_... instead of of_reset_control_get_...). regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html