Return-path: Received: from mail-yw0-f174.google.com ([209.85.161.174]:33372 "EHLO mail-yw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754344AbcDTBYH (ORCPT ); Tue, 19 Apr 2016 21:24:07 -0400 Received: by mail-yw0-f174.google.com with SMTP id t10so38137668ywa.0 for ; Tue, 19 Apr 2016 18:24:07 -0700 (PDT) Subject: Re: [PATCH 1/4] NFC: trf7970a: Add support for gpio as SS To: linux-wireless References: <1461008921-15100-1-git-send-email-geoff@kuvee.com> <1461008921-15100-2-git-send-email-geoff@kuvee.com> Cc: Julian Calaby , Lauro Ramos Venancio , Aloisio Almeida Jr , Samuel Ortiz , mgreer@animalcreek.com, Justin Bronder From: Geoffrey Lansberry Message-ID: <5716DA34.3070201@kuvee.com> (sfid-20160420_032421_431358_078D5D27) Date: Tue, 19 Apr 2016 21:24:04 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: As Julian suggests, this is handled by the cs-gpios property, so we will drop this patch, but keep the other three active. Thanks for the suggestion. > > On Mon, Apr 18, 2016 at 8:07 PM, Julian Calaby > > wrote: > > Hi Geoff, > > On Tue, Apr 19, 2016 at 5:48 AM, Geoff Lansberry > wrote: > > Signed-off-by: Geoff Lansberry > > > Can't you just use the cs-gpios property? This should require no > driver changes. > > This is described here: > > https://www.kernel.org/doc/Documentation/devicetree/bindings/spi/spi-bus.txt > > Thanks, > > Julian Calaby > > > > --- > > .../devicetree/bindings/net/nfc/trf7970a.txt | 2 ++ > > drivers/nfc/trf7970a.c | 33 ++++++++++++++++++++-- > > 2 files changed, 33 insertions(+), 2 deletions(-) > > > > diff --git > a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt > b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt > > index 32b35a0..09c5056 100644 > > --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt > > +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt > > @@ -7,6 +7,7 @@ Required properties: > > - interrupts: A single interrupt specifier. > > - ti,enable-gpios: Two GPIO entries used for 'EN' and 'EN2' > pins on the > > TRF7970A. > > +- ti,ss-gpio: GPIO entry used for active low SS (spi slave > select) on the TRF7970A > > - vin-supply: Regulator for supply voltage to VIN pin > > > > Optional SoC Specific Properties: > > @@ -37,6 +38,7 @@ Example (for ARM-based BeagleBone with > TRF7970A on SPI1): > > interrupts = <14 0>; > > ti,enable-gpios = <&gpio2 2 GPIO_ACTIVE_LOW>, > > <&gpio2 5 GPIO_ACTIVE_LOW>; > > + ti,ss-gpio = <&gpio2 4 GPIO_ACTIVE_HIGH>; > > vin-supply = <&ldo3_reg>; > > vin-voltage-override = <5000000>; > > autosuspend-delay = <30000>; > > diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c > > index 10842b7..2c3530a 100644 > > --- a/drivers/nfc/trf7970a.c > > +++ b/drivers/nfc/trf7970a.c > > @@ -450,6 +450,7 @@ struct trf7970a { > > bool adjust_resp_len; > > int en2_gpio; > > int en_gpio; > > + int ss_gpio; > > struct mutex lock; > > unsigned int timeout; > > bool ignore_timeout; > > @@ -462,9 +463,11 @@ static int trf7970a_cmd(struct trf7970a > *trf, u8 opcode) > > u8 cmd = TRF7970A_CMD_BIT_CTRL | > TRF7970A_CMD_BIT_OPCODE(opcode); > > int ret; > > > > + gpio_set_value(trf->ss_gpio, 0); > > dev_dbg(trf->dev, "cmd: 0x%x\n", cmd); > > > > ret = spi_write(trf->spi, &cmd, 1); > > + gpio_set_value(trf->ss_gpio, 1); > > if (ret) > > dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", > __func__, cmd, > > ret); > > @@ -476,7 +479,9 @@ static int trf7970a_read(struct trf7970a > *trf, u8 reg, u8 *val) > > u8 addr = TRF7970A_CMD_BIT_RW | reg; > > int ret; > > > > + gpio_set_value(trf->ss_gpio, 0); > > ret = spi_write_then_read(trf->spi, &addr, 1, val, 1); > > + gpio_set_value(trf->ss_gpio, 1); > > if (ret) > > dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", > __func__, addr, > > ret); > > @@ -493,6 +498,7 @@ static int trf7970a_read_cont(struct > trf7970a *trf, u8 reg, u8 *buf, size_t len) > > struct spi_message m; > > int ret; > > > > + gpio_set_value(trf->ss_gpio, 0); > > dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len); > > > > spi_message_init(&m); > > @@ -508,6 +514,7 @@ static int trf7970a_read_cont(struct > trf7970a *trf, u8 reg, u8 *buf, size_t len) > > spi_message_add_tail(&t[1], &m); > > > > ret = spi_sync(trf->spi, &m); > > + gpio_set_value(trf->ss_gpio, 1); > > if (ret) > > dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", > __func__, addr, > > ret); > > @@ -519,9 +526,11 @@ static int trf7970a_write(struct trf7970a > *trf, u8 reg, u8 val) > > u8 buf[2] = { reg, val }; > > int ret; > > > > + gpio_set_value(trf->ss_gpio, 0); > > dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val); > > > > ret = spi_write(trf->spi, buf, 2); > > + gpio_set_value(trf->ss_gpio, 1); > > if (ret) > > dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: > %d\n", __func__, > > buf[0], buf[1], ret); > > @@ -535,6 +544,7 @@ static int trf7970a_read_irqstatus(struct > trf7970a *trf, u8 *status) > > u8 buf[2]; > > u8 addr; > > > > + gpio_set_value(trf->ss_gpio, 0); > > addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW; > > > > if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) { > > @@ -544,6 +554,7 @@ static int trf7970a_read_irqstatus(struct > trf7970a *trf, u8 *status) > > ret = spi_write_then_read(trf->spi, &addr, 1, > buf, 1); > > } > > > > + gpio_set_value(trf->ss_gpio, 1); > > if (ret) > > dev_err(trf->dev, "%s - irqstatus: Status read > failed: %d\n", > > __func__, ret); > > @@ -559,6 +570,7 @@ static int trf7970a_read_target_proto(struct > trf7970a *trf, u8 *target_proto) > > u8 buf[2]; > > u8 addr; > > > > + gpio_set_value(trf->ss_gpio, 0); > > addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW | > > TRF7970A_CMD_BIT_CONTINUOUS; > > > > @@ -569,6 +581,7 @@ static int trf7970a_read_target_proto(struct > trf7970a *trf, u8 *target_proto) > > else > > *target_proto = buf[0]; > > > > + gpio_set_value(trf->ss_gpio, 1); > > return ret; > > } > > > > @@ -663,6 +676,7 @@ static int trf7970a_transmit(struct trf7970a > *trf, struct sk_buff *skb, > > print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE, > > 16, 1, skb->data, len, false); > > > > + gpio_set_value(trf->ss_gpio, 0); > > spi_message_init(&m); > > > > memset(&t, 0, sizeof(t)); > > @@ -679,7 +693,7 @@ static int trf7970a_transmit(struct trf7970a > *trf, struct sk_buff *skb, > > if (ret) { > > dev_err(trf->dev, "%s - Can't send tx data: > %d\n", __func__, > > ret); > > - return ret; > > + goto out_err; > > } > > > > skb_pull(skb, len); > > @@ -706,7 +720,9 @@ static int trf7970a_transmit(struct trf7970a > *trf, struct sk_buff *skb, > > > > schedule_delayed_work(&trf->timeout_work, > msecs_to_jiffies(timeout)); > > > > - return 0; > > +out_err: > > + gpio_set_value(trf->ss_gpio, 1); > > + return ret; > > } > > > > static void trf7970a_fill_fifo(struct trf7970a *trf) > > @@ -2039,6 +2055,19 @@ static int trf7970a_probe(struct > spi_device *spi) > > return ret; > > } > > > > + trf->ss_gpio = of_get_named_gpio(np, "ti,ss-gpio", 0); > > + if (!gpio_is_valid(trf->ss_gpio)) { > > + dev_err(trf->dev, "No SS GPIO property\n"); > > + return trf->ss_gpio; > > + } > > + > > + ret = devm_gpio_request_one(trf->dev, trf->ss_gpio, > > + GPIOF_DIR_OUT | GPIOF_INIT_HIGH, > "trf7970a SS"); > > + if (ret) { > > + dev_err(trf->dev, "Can't request SS GPIO: %d\n", > ret); > > + return ret; > > + } > > + > > if (of_property_read_bool(np, "en2-rf-quirk")) > > trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW; > > > > -- > > 1.9.1 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe > linux-wireless" in > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > -- > Julian Calaby > > Email: julian.calaby@gmail.com > Profile: http://www.google.com/profiles/julian.calaby/ > > > > > -- > Geoff Lansberry > > > Engineering Guy > Kuvée, Inc > 125 Kingston St., 3rd Floor > Boston, MA 02111 > 1-617-290-1118 (m) > geoff.lansberry (skype) > http://www.kuvee.com > >