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[3/4] NFC: trf7970a: add device tree option for 27MHz clock

Message ID 1461008921-15100-4-git-send-email-geoff@kuvee.com (mailing list archive)
State Rejected
Delegated to: Samuel Ortiz
Headers show

Commit Message

Geoff Lansberry April 18, 2016, 7:48 p.m. UTC 
Signed-off-by: Geoff Lansberry <geoff@kuvee.com>
---
 .../devicetree/bindings/net/nfc/trf7970a.txt       |  2 ++
 drivers/nfc/trf7970a.c                             | 28 +++++++++++++---------
 2 files changed, 19 insertions(+), 11 deletions(-)

Comments

Julian Calaby April 19, 2016, 12:11 a.m. UTC | #1 
Hi Geoff,

On Tue, Apr 19, 2016 at 5:48 AM, Geoff Lansberry <geoff@kuvee.com> wrote:
> Signed-off-by: Geoff Lansberry <geoff@kuvee.com>

You should add the description you had in your cover letter to the patches also.

> ---
>  .../devicetree/bindings/net/nfc/trf7970a.txt       |  2 ++
>  drivers/nfc/trf7970a.c                             | 28 +++++++++++++---------
>  2 files changed, 19 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> index 09c5056..bf25f39 100644
> --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
> @@ -22,6 +22,7 @@ Optional SoC Specific Properties:
>  - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum
>    where an extra byte is returned by Read Multiple Block commands issued
>    to Type 5 tags.
> +- crystal_27mhz: Set to specify that the input frequency to the trf7970a is 27.12MHz

Does the trf7970a only operate at the default or 27.12MHz, or can it
operate at any frequency? If it's the latter, would it make sense to
specify this using the clock framework and some fixed-factor clock?

Thanks,

Julian Calaby


>  Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>
> @@ -45,6 +46,7 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>                 irq-status-read-quirk;
>                 en2-rf-quirk;
>                 t5t-rmb-extra-byte-quirk;
> +               crystal_27mhz;
>                 status = "okay";
>         };
>  };
> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
> index 447b6c9..74210f9 100644
> --- a/drivers/nfc/trf7970a.c
> +++ b/drivers/nfc/trf7970a.c
> @@ -1072,12 +1072,11 @@ static int trf7970a_init(struct trf7970a *trf)
>
>         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
>
> -       ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
> +       ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
> +                       trf->modulator_sys_clk_ctrl);
>         if (ret)
>                 goto err_out;
>
> -       trf->modulator_sys_clk_ctrl = 0;
> -
>         ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
>                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
>                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
> @@ -1194,30 +1193,32 @@ static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
>
>         dev_dbg(trf->dev, "rf technology: %d\n", tech);
>
> +       trf->modulator_sys_clk_ctrl = (trf->modulator_sys_clk_ctrl&0xF8);
> +
>         switch (tech) {
>         case NFC_DIGITAL_RF_TECH_106A:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
>                 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
>                 break;
>         case NFC_DIGITAL_RF_TECH_106B:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
>                 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
>                 break;
>         case NFC_DIGITAL_RF_TECH_212F:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
>                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
>                 break;
>         case NFC_DIGITAL_RF_TECH_424F:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
>                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
>                 break;
>         case NFC_DIGITAL_RF_TECH_ISO15693:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
>                 trf->guard_time = TRF7970A_GUARD_TIME_15693;
>                 break;
>         default:
> @@ -1582,22 +1583,24 @@ static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
>
>         dev_dbg(trf->dev, "rf technology: %d\n", tech);
>
> +       trf->modulator_sys_clk_ctrl = (trf->modulator_sys_clk_ctrl&0xF8);
> +
>         switch (tech) {
>         case NFC_DIGITAL_RF_TECH_106A:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>                         TRF7970A_ISO_CTRL_NFC_CE |
>                         TRF7970A_ISO_CTRL_NFC_CE_14443A;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
>                 break;
>         case NFC_DIGITAL_RF_TECH_212F:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>                         TRF7970A_ISO_CTRL_NFC_NFCF_212;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
>                 break;
>         case NFC_DIGITAL_RF_TECH_424F:
>                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
>                         TRF7970A_ISO_CTRL_NFC_NFCF_424;
> -               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
> +               trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
>                 break;
>         default:
>                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
> @@ -2072,6 +2075,9 @@ static int trf7970a_probe(struct spi_device *spi)
>                 return ret;
>         }
>
> +       if (of_property_read_bool(np, "crystal_27MHz"))
> +               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
> +
>         if (of_property_read_bool(np, "en2-rf-quirk"))
>                 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
>
> --
> 1.9.1
>
> --
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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
index 09c5056..bf25f39 100644
--- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
+++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
@@ -22,6 +22,7 @@  Optional SoC Specific Properties:
 - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum
   where an extra byte is returned by Read Multiple Block commands issued
   to Type 5 tags.
+- crystal_27mhz: Set to specify that the input frequency to the trf7970a is 27.12MHz
 
 Example (for ARM-based BeagleBone with TRF7970A on SPI1):
 
@@ -45,6 +46,7 @@  Example (for ARM-based BeagleBone with TRF7970A on SPI1):
 		irq-status-read-quirk;
 		en2-rf-quirk;
 		t5t-rmb-extra-byte-quirk;
+		crystal_27mhz;
 		status = "okay";
 	};
 };
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 447b6c9..74210f9 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -1072,12 +1072,11 @@  static int trf7970a_init(struct trf7970a *trf)
 
 	trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
 
-	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
+	ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
+			trf->modulator_sys_clk_ctrl);
 	if (ret)
 		goto err_out;
 
-	trf->modulator_sys_clk_ctrl = 0;
-
 	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
@@ -1194,30 +1193,32 @@  static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
 
 	dev_dbg(trf->dev, "rf technology: %d\n", tech);
 
+	trf->modulator_sys_clk_ctrl = (trf->modulator_sys_clk_ctrl&0xF8);
+
 	switch (tech) {
 	case NFC_DIGITAL_RF_TECH_106A:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
 		break;
 	case NFC_DIGITAL_RF_TECH_106B:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
 		break;
 	case NFC_DIGITAL_RF_TECH_212F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
 		break;
 	case NFC_DIGITAL_RF_TECH_424F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
 		trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
 		break;
 	case NFC_DIGITAL_RF_TECH_ISO15693:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
 		trf->guard_time = TRF7970A_GUARD_TIME_15693;
 		break;
 	default:
@@ -1582,22 +1583,24 @@  static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
 
 	dev_dbg(trf->dev, "rf technology: %d\n", tech);
 
+	trf->modulator_sys_clk_ctrl = (trf->modulator_sys_clk_ctrl&0xF8);
+
 	switch (tech) {
 	case NFC_DIGITAL_RF_TECH_106A:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_CE |
 			TRF7970A_ISO_CTRL_NFC_CE_14443A;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_OOK;
 		break;
 	case NFC_DIGITAL_RF_TECH_212F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_NFCF_212;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
 		break;
 	case NFC_DIGITAL_RF_TECH_424F:
 		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
 			TRF7970A_ISO_CTRL_NFC_NFCF_424;
-		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		trf->modulator_sys_clk_ctrl |= TRF7970A_MODULATOR_DEPTH_ASK10;
 		break;
 	default:
 		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
@@ -2072,6 +2075,9 @@  static int trf7970a_probe(struct spi_device *spi)
 		return ret;
 	}
 
+	if (of_property_read_bool(np, "crystal_27MHz"))
+		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_27MHZ;
+
 	if (of_property_read_bool(np, "en2-rf-quirk"))
 		trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;