The TRF7970A has configuration options to support hardware designs
which use a 27.12MHz clock. This commit adds a device tree option
'clock-frequency' to support configuring the this chip for default
13.56MHz clock or the optional 27.12MHz clock.
Signed-off-by: Geoff Lansberry
---
.../devicetree/bindings/net/nfc/trf7970a.txt | 2 +
drivers/nfc/trf7970a.c | 50 +-
2 files changed, 41 insertions(+), 11 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
index 32b35a0..8b01fc81 100644
--- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
+++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
@@ -21,6 +21,7 @@ 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.
+- clock-frequency: Set to specify that the input frequency to the trf7970a is
1356Hz or 2712Hz
Example (for ARM-based BeagleBone with TRF7970A on SPI1):
@@ -43,6 +44,7 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1):
irq-status-read-quirk;
en2-rf-quirk;
t5t-rmb-extra-byte-quirk;
+ clock-frequency = <2712>;
status = "okay";
};
};
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 26c9dbb..b1cd4ef 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -124,6 +124,9 @@
NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
#define TRF7970A_AUTOSUSPEND_DELAY 3 /* 30 seconds */
+#define TRF7970A_13MHZ_CLOCK_FREQUENCY 1356
+#define TRF7970A_27MHZ_CLOCK_FREQUENCY 2712
+
#define TRF7970A_RX_SKB_ALLOC_SIZE 256
@@ -1056,12 +1059,11 @@ 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);
@@ -1181,27 +1183,37 @@ static int trf7970a_in_config_rf_tech(struct trf7970a
*trf, int tech)
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 =
+ (trf->modulator_sys_clk_ctrl & 0xf8) |
+ 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 =
+ (trf->modulator_sys_clk_ctrl & 0xf8) |
+ 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 =
+ (trf->modulator_sys_clk_ctrl & 0xf8) |
+ 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 =
+ (trf->modulator_sys_clk_ctrl & 0xf8) |
+ 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 =
+ (trf->modulator_sys_clk_ctrl & 0xf8) |
+ TRF7970A_MODULATOR_DEPTH_OOK;
trf->guard_time = TRF7970A_GUARD_TIME_15693;
break;
default:
@@ -1571,17 +1583,23 @@ static int trf7970a_tg_config_rf_tech(struct trf7970a
*trf, int tech)
trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |