Hi Thor, thank you for the patch. A few comments below: On Wed, 2017-02-15 at 15:50 -0600, thor.thayer@xxxxxxxxxxxxxxx wrote: > From: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx> > > This patch adds the reset controller functionality to the Arria10 > System Resource Manager. > > Signed-off-by: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx> > --- > MAINTAINERS | 1 + > drivers/reset/Kconfig | 7 ++ > drivers/reset/Makefile | 1 + > drivers/reset/reset-a10sr.c | 176 ++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 185 insertions(+) > create mode 100644 drivers/reset/reset-a10sr.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index a2c74db..3265cb2 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -655,6 +655,7 @@ F: drivers/gpio/gpio-altera-a10sr.c > F: drivers/mfd/altera-a10sr.c > F: include/linux/mfd/altera-a10sr.h > F: include/dt-bindings/reset/altr,rst-mgr-a10sr.h > +F: drivers/reset/reset-a10sr.c > > ALTERA TRIPLE SPEED ETHERNET DRIVER > M: Vince Bridgers <vbridger@xxxxxxxxxxxxxxxxxxxxx> > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > index f4cdfe9..b821d1b 100644 > --- a/drivers/reset/Kconfig > +++ b/drivers/reset/Kconfig > @@ -39,6 +39,13 @@ config RESET_MESON > help > This enables the reset driver for Amlogic Meson SoCs. > > +config ALTERA_A10SR_RESET Please follow the RESET_<SoC> convention and sort alphabetically. > + tristate "Altera Arria10 System Resource Reset" > + depends on MFD_ALTERA_A10SR > + help > + This option enables support for the external reset functions for > + peripheral PHYs on the Altera Arria10 System Resource Chip. > + > config RESET_OXNAS > bool > > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > index 2cd3f6c..d6a2a87 100644 > --- a/drivers/reset/Makefile > +++ b/drivers/reset/Makefile > @@ -15,3 +15,4 @@ obj-$(CONFIG_TI_SYSCON_RESET) += reset-ti-syscon.o > obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o > obj-$(CONFIG_RESET_ZX2967) += reset-zx2967.o > obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o > +obj-$(CONFIG_ALTERA_A10SR_RESET) += reset-a10sr.o > diff --git a/drivers/reset/reset-a10sr.c b/drivers/reset/reset-a10sr.c > new file mode 100644 > index 0000000..ed058f3 > --- /dev/null > +++ b/drivers/reset/reset-a10sr.c > @@ -0,0 +1,176 @@ > +/* > + * Copyright Intel Corporation (C) 2017. All Rights Reserved > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope 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. > + * > + * You should have received a copy of the GNU General Public License along with > + * this program. If not, see <http://www.gnu.org/licenses/>. > + * > + * Reset driver for Altera Arria10 MAX5 System Resource Chip > + * > + * Adapted from reset-socfpga.c > + */ > + > +#include <linux/err.h> > +#include <linux/io.h> This is not used. > +#include <linux/mfd/altera-a10sr.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/reset-controller.h> > +#include <linux/types.h> > + > +#include <dt-bindings/reset/altr,rst-mgr-a10sr.h> > + > +/* Number of A10 System Controller Resets */ > +#define A10SR_RESETS 16 So 16 resets... > +struct a10sr_reset { > + struct reset_controller_dev rcdev; > + struct regmap *regmap; > +}; > + > +static inline struct a10sr_reset *to_a10sr_rst(struct reset_controller_dev *rc) > +{ > + return container_of(rc, struct a10sr_reset, rcdev); > +} > + > +static inline int a10sr_reset_shift(unsigned long id) > +{ > + switch (id) { > + case A10SR_RESET_ENET_HPS: > + return 1; > + case A10SR_RESET_PCIE: > + case A10SR_RESET_FILE: > + case A10SR_RESET_BQSPI: > + case A10SR_RESET_USB: > + return id + 11; ... but only 5 are handled. What about the other 11? Could you point me to documentation for this reset controller? > + default: > + return -EINVAL; > + } > +} > + > +static int a10sr_reset_update(struct reset_controller_dev *rcdev, > + unsigned long id, bool assert) > +{ > + struct a10sr_reset *a10r = to_a10sr_rst(rcdev); > + int offset = a10sr_reset_shift(id); > + u8 mask = ALTR_A10SR_REG_BIT_MASK(offset); > + int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset); > + > + if (id >= rcdev->nr_resets) > + return -EINVAL; Checking the id is not necessary. The ops are called with rstc->id, which was checked in of_reset_simple_xlate. > + return regmap_update_bits(a10r->regmap, index, mask, assert ? 0 : mask); > +} > + > +static int a10sr_reset_assert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return a10sr_reset_update(rcdev, id, true); > +} > + > +static int a10sr_reset_deassert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return a10sr_reset_update(rcdev, id, false); > +} > + > +static int a10sr_reset_status(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + int error; > + struct a10sr_reset *a10r = to_a10sr_rst(rcdev); > + int offset = a10sr_reset_shift(id); > + u8 mask = ALTR_A10SR_REG_BIT_MASK(offset); > + int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset); > + unsigned int value; > + > + if (id >= rcdev->nr_resets) > + return -EINVAL; Same here. reset_status should never be called with an invalid id. > + error = regmap_read(a10r->regmap, index, &value); > + if (error < 0) > + return -ENOMEM; Why ENOMEM? Just propagate the error. > + > + return !!(value & mask); > +} > + > +static const struct reset_control_ops a10sr_reset_ops = { > + .assert = a10sr_reset_assert, > + .deassert = a10sr_reset_deassert, > + .status = a10sr_reset_status, > +}; > + > +static const struct of_device_id a10sr_reset_of_match[]; Avoid forward declarations. Just move a10sr_reset_of_match up here if needed. Although I don't think this is necessary, see below. > +static int a10sr_reset_probe(struct platform_device *pdev) > +{ > + struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent); > + struct a10sr_reset *a10r; > + struct device *dev = &pdev->dev; > + struct device_node *np = dev->of_node; Here np is assigned to pdev->dev.of_node. > + /* Ensure we have a valid DT entry. */ > + np = of_find_matching_node(NULL, a10sr_reset_of_match); And here it is overwritten again. Shouldn't those be the same anyway? I think this assignment and the DT entry check could be removed. > + if (!np) { > + dev_err(&pdev->dev, "A10 Reset DT Entry not found\n"); > + return -EINVAL; > + } > + > + if (!of_find_property(np, "#reset-cells", NULL)) { > + dev_err(&pdev->dev, "%s missing #reset-cells property\n", > + np->full_name); > + return -EINVAL; > + } This is unnecessary. If #reset-cells is missing, the reset lookups will fail. > + a10r = devm_kzalloc(&pdev->dev, sizeof(struct a10sr_reset), > + GFP_KERNEL); > + if (!a10r) > + return -ENOMEM; > + > + a10r->rcdev.owner = THIS_MODULE; > + a10r->rcdev.nr_resets = A10SR_RESETS; > + a10r->rcdev.ops = &a10sr_reset_ops; > + a10r->rcdev.of_node = np; > + a10r->regmap = a10sr->regmap; > + > + platform_set_drvdata(pdev, a10r); > + > + return devm_reset_controller_register(dev, &a10r->rcdev); > +} > + > +static int a10sr_reset_remove(struct platform_device *pdev) > +{ > + struct a10sr_reset *a10r = platform_get_drvdata(pdev); > + > + reset_controller_unregister(&a10r->rcdev); Since you use the devm_ variant of reset_controller_register above, this happens automatically. You can drop a10sr_reset_remove completely. > + > + return 0; > +} > + > +static const struct of_device_id a10sr_reset_of_match[] = { > + { .compatible = "altr,a10sr-reset" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, a10sr_reset_of_match); > + > +static struct platform_driver a10sr_reset_driver = { > + .probe = a10sr_reset_probe, > + .remove = a10sr_reset_remove, > + .driver = { > + .name = "altr_a10sr_reset", > + .owner = THIS_MODULE, Assigning .owner is not necessary anymore, __platform_driver_register does this. > + }, > +}; > +module_platform_driver(a10sr_reset_driver); > + > +MODULE_AUTHOR("Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Altera Arria10 System Resource Reset Controller Driver"); > +MODULE_LICENSE("GPL v2"); regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
