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-rw-r--r--drivers/media/video/cx23885/cx23888-ir.c1063
1 files changed, 1034 insertions, 29 deletions
diff --git a/drivers/media/video/cx23885/cx23888-ir.c b/drivers/media/video/cx23885/cx23888-ir.c
index 12df0e3a235..e8d949ae06b 100644
--- a/drivers/media/video/cx23885/cx23888-ir.c
+++ b/drivers/media/video/cx23885/cx23888-ir.c
@@ -21,25 +21,79 @@
* 02110-1301, USA.
*/
+#include <linux/kfifo.h>
+
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include "cx23885.h"
+static unsigned int ir_888_debug;
+module_param(ir_888_debug, int, 0644);
+MODULE_PARM_DESC(ir_888_debug, "enable debug messages [CX23888 IR controller]");
+
#define CX23888_IR_REG_BASE 0x170000
/*
* These CX23888 register offsets have a straightforward one to one mapping
* to the CX23885 register offsets of 0x200 through 0x218
*/
#define CX23888_IR_CNTRL_REG 0x170000
+#define CNTRL_WIN_3_3 0x00000000
+#define CNTRL_WIN_4_3 0x00000001
+#define CNTRL_WIN_3_4 0x00000002
+#define CNTRL_WIN_4_4 0x00000003
+#define CNTRL_WIN 0x00000003
+#define CNTRL_EDG_NONE 0x00000000
+#define CNTRL_EDG_FALL 0x00000004
+#define CNTRL_EDG_RISE 0x00000008
+#define CNTRL_EDG_BOTH 0x0000000C
+#define CNTRL_EDG 0x0000000C
+#define CNTRL_DMD 0x00000010
+#define CNTRL_MOD 0x00000020
+#define CNTRL_RFE 0x00000040
+#define CNTRL_TFE 0x00000080
+#define CNTRL_RXE 0x00000100
+#define CNTRL_TXE 0x00000200
+#define CNTRL_RIC 0x00000400
+#define CNTRL_TIC 0x00000800
+#define CNTRL_CPL 0x00001000
+#define CNTRL_LBM 0x00002000
+#define CNTRL_R 0x00004000
+
#define CX23888_IR_TXCLK_REG 0x170004
+#define TXCLK_TCD 0x0000FFFF
+
#define CX23888_IR_RXCLK_REG 0x170008
+#define RXCLK_RCD 0x0000FFFF
+
#define CX23888_IR_CDUTY_REG 0x17000C
+#define CDUTY_CDC 0x0000000F
+
#define CX23888_IR_STATS_REG 0x170010
+#define STATS_RTO 0x00000001
+#define STATS_ROR 0x00000002
+#define STATS_RBY 0x00000004
+#define STATS_TBY 0x00000008
+#define STATS_RSR 0x00000010
+#define STATS_TSR 0x00000020
+
#define CX23888_IR_IRQEN_REG 0x170014
+#define IRQEN_RTE 0x00000001
+#define IRQEN_ROE 0x00000002
+#define IRQEN_RSE 0x00000010
+#define IRQEN_TSE 0x00000020
+
#define CX23888_IR_FILTR_REG 0x170018
+#define FILTR_LPF 0x0000FFFF
+
/* This register doesn't follow the pattern; it's 0x23C on a CX23885 */
#define CX23888_IR_FIFO_REG 0x170040
+#define FIFO_RXTX 0x0000FFFF
+#define FIFO_RXTX_LVL 0x00010000
+#define FIFO_RXTX_RTO 0x0001FFFF
+#define FIFO_RX_NDV 0x00020000
+#define FIFO_RX_DEPTH 8
+#define FIFO_TX_DEPTH 8
/* CX23888 unique registers */
#define CX23888_IR_SEEDP_REG 0x17001C
@@ -53,12 +107,32 @@
#define CX23888_IR_DPIPG_REG 0x17003C
#define CX23888_IR_LEARN_REG 0x170044
+#define CX23888_VIDCLK_FREQ 108000000 /* 108 MHz, BT.656 */
+#define CX23888_IR_REFCLK_FREQ (CX23888_VIDCLK_FREQ/2)
+
+#define CX23888_IR_RX_KFIFO_SIZE (512 * sizeof(u32))
+#define CX23888_IR_TX_KFIFO_SIZE (512 * sizeof(u32))
struct cx23888_ir_state {
struct v4l2_subdev sd;
struct cx23885_dev *dev;
u32 id;
u32 rev;
+
+ struct v4l2_subdev_ir_parameters rx_params;
+ struct mutex rx_params_lock;
+ atomic_t rxclk_divider;
+ atomic_t rx_invert;
+
+ struct kfifo *rx_kfifo;
+ spinlock_t rx_kfifo_lock;
+
+ struct v4l2_subdev_ir_parameters tx_params;
+ struct mutex tx_params_lock;
+ atomic_t txclk_divider;
+
+ struct kfifo *tx_kfifo;
+ spinlock_t tx_kfifo_lock;
};
static inline struct cx23888_ir_state *to_state(struct v4l2_subdev *sd)
@@ -66,59 +140,903 @@ static inline struct cx23888_ir_state *to_state(struct v4l2_subdev *sd)
return v4l2_get_subdevdata(sd);
}
-static int cx23888_ir_write(struct cx23885_dev *dev, u32 addr, u8 value)
+/*
+ * IR register block read and write functions
+ */
+static
+inline int cx23888_ir_write4(struct cx23885_dev *dev, u32 addr, u32 value)
{
- u32 reg = (addr & ~3);
- int shift = (addr & 3) * 8;
- u32 x = cx_read(reg);
+ cx_write(addr, value);
+ return 0;
+}
+
+static inline u32 cx23888_ir_read4(struct cx23885_dev *dev, u32 addr)
+{
+ return cx_read(addr);
+}
- x = (x & ~(0xff << shift)) | ((u32)value << shift);
- cx_write(reg, x);
+static inline int cx23888_ir_and_or4(struct cx23885_dev *dev, u32 addr,
+ u32 and_mask, u32 or_value)
+{
+ cx_andor(addr, ~and_mask, or_value);
return 0;
}
-static
-inline int cx23888_ir_write4(struct cx23885_dev *dev, u32 addr, u32 value)
+/*
+ * Rx and Tx Clock Divider register computations
+ *
+ * Note the largest clock divider value of 0xffff corresponds to:
+ * (0xffff + 1) * 1000 / 108/2 MHz = 1,213,629.629... ns
+ * which fits in 21 bits, so we'll use unsigned int for time arguments.
+ */
+static inline u16 count_to_clock_divider(unsigned int d)
{
- cx_write(addr, value);
+ if (d > RXCLK_RCD+1)
+ d = RXCLK_RCD;
+ else if (d < 2)
+ d = 1;
+ else
+ d--;
+ return (u16) d;
+}
+
+static inline u16 ns_to_clock_divider(unsigned int ns)
+{
+ return count_to_clock_divider(
+ DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ/1000000 * ns, 1000));
+}
+
+static inline unsigned int clock_divider_to_ns(unsigned int divider)
+{
+ /* Period of the Rx or Tx clock in ns */
+ return DIV_ROUND_CLOSEST((divider + 1) * 1000,
+ CX23888_IR_REFCLK_FREQ/1000000);
+}
+
+static inline u16 carrier_freq_to_clock_divider(unsigned int freq)
+{
+ return count_to_clock_divider(
+ DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, freq * 16));
+}
+
+static inline unsigned int clock_divider_to_carrier_freq(unsigned int divider)
+{
+ return DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, (divider + 1) * 16);
+}
+
+static inline u16 freq_to_clock_divider(unsigned int freq,
+ unsigned int rollovers)
+{
+ return count_to_clock_divider(
+ DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, freq * rollovers));
+}
+
+static inline unsigned int clock_divider_to_freq(unsigned int divider,
+ unsigned int rollovers)
+{
+ return DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ,
+ (divider + 1) * rollovers);
+}
+
+/*
+ * Low Pass Filter register calculations
+ *
+ * Note the largest count value of 0xffff corresponds to:
+ * 0xffff * 1000 / 108/2 MHz = 1,213,611.11... ns
+ * which fits in 21 bits, so we'll use unsigned int for time arguments.
+ */
+static inline u16 count_to_lpf_count(unsigned int d)
+{
+ if (d > FILTR_LPF)
+ d = FILTR_LPF;
+ else if (d < 4)
+ d = 0;
+ return (u16) d;
+}
+
+static inline u16 ns_to_lpf_count(unsigned int ns)
+{
+ return count_to_lpf_count(
+ DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ/1000000 * ns, 1000));
+}
+
+static inline unsigned int lpf_count_to_ns(unsigned int count)
+{
+ /* Duration of the Low Pass Filter rejection window in ns */
+ return DIV_ROUND_CLOSEST(count * 1000, CX23888_IR_REFCLK_FREQ/1000000);
+}
+
+static inline unsigned int lpf_count_to_us(unsigned int count)
+{
+ /* Duration of the Low Pass Filter rejection window in us */
+ return DIV_ROUND_CLOSEST(count, CX23888_IR_REFCLK_FREQ/1000000);
+}
+
+/*
+ * FIFO register pulse width count compuations
+ */
+static u32 clock_divider_to_resolution(u16 divider)
+{
+ /*
+ * Resolution is the duration of 1 tick of the readable portion of
+ * of the pulse width counter as read from the FIFO. The two lsb's are
+ * not readable, hence the << 2. This function returns ns.
+ */
+ return DIV_ROUND_CLOSEST((1 << 2) * ((u32) divider + 1) * 1000,
+ CX23888_IR_REFCLK_FREQ/1000000);
+}
+
+static u64 pulse_width_count_to_ns(u16 count, u16 divider)
+{
+ u64 n;
+ u32 rem;
+
+ /*
+ * The 2 lsb's of the pulse width timer count are not readable, hence
+ * the (count << 2) | 0x3
+ */
+ n = (((u64) count << 2) | 0x3) * (divider + 1) * 1000; /* millicycles */
+ rem = do_div(n, CX23888_IR_REFCLK_FREQ/1000000); /* / MHz => ns */
+ if (rem >= CX23888_IR_REFCLK_FREQ/1000000/2)
+ n++;
+ return n;
+}
+
+static unsigned int pulse_width_count_to_us(u16 count, u16 divider)
+{
+ u64 n;
+ u32 rem;
+
+ /*
+ * The 2 lsb's of the pulse width timer count are not readable, hence
+ * the (count << 2) | 0x3
+ */
+ n = (((u64) count << 2) | 0x3) * (divider + 1); /* cycles */
+ rem = do_div(n, CX23888_IR_REFCLK_FREQ/1000000); /* / MHz => us */
+ if (rem >= CX23888_IR_REFCLK_FREQ/1000000/2)
+ n++;
+ return (unsigned int) n;
+}
+
+/*
+ * Pulse Clocks computations: Combined Pulse Width Count & Rx Clock Counts
+ *
+ * The total pulse clock count is an 18 bit pulse width timer count as the most
+ * significant part and (up to) 16 bit clock divider count as a modulus.
+ * When the Rx clock divider ticks down to 0, it increments the 18 bit pulse
+ * width timer count's least significant bit.
+ */
+static u64 ns_to_pulse_clocks(u32 ns)
+{
+ u64 clocks;
+ u32 rem;
+ clocks = CX23888_IR_REFCLK_FREQ/1000000 * (u64) ns; /* millicycles */
+ rem = do_div(clocks, 1000); /* /1000 = cycles */
+ if (rem >= 1000/2)
+ clocks++;
+ return clocks;
+}
+
+static u16 pulse_clocks_to_clock_divider(u64 count)
+{
+ u32 rem;
+
+ rem = do_div(count, (FIFO_RXTX << 2) | 0x3);
+
+ /* net result needs to be rounded down and decremented by 1 */
+ if (count > RXCLK_RCD+1)
+ count = RXCLK_RCD;
+ else if (count < 2)
+ count = 1;
+ else
+ count--;
+ return (u16) count;
+}
+
+/*
+ * IR Control Register helpers
+ */
+enum tx_fifo_watermark {
+ TX_FIFO_HALF_EMPTY = 0,
+ TX_FIFO_EMPTY = CNTRL_TIC,
+};
+
+enum rx_fifo_watermark {
+ RX_FIFO_HALF_FULL = 0,
+ RX_FIFO_NOT_EMPTY = CNTRL_RIC,
+};
+
+static inline void control_tx_irq_watermark(struct cx23885_dev *dev,
+ enum tx_fifo_watermark level)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_TIC, level);
+}
+
+static inline void control_rx_irq_watermark(struct cx23885_dev *dev,
+ enum rx_fifo_watermark level)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_RIC, level);
+}
+
+static inline void control_tx_enable(struct cx23885_dev *dev, bool enable)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~(CNTRL_TXE | CNTRL_TFE),
+ enable ? (CNTRL_TXE | CNTRL_TFE) : 0);
+}
+
+static inline void control_rx_enable(struct cx23885_dev *dev, bool enable)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~(CNTRL_RXE | CNTRL_RFE),
+ enable ? (CNTRL_RXE | CNTRL_RFE) : 0);
+}
+
+static inline void control_tx_modulation_enable(struct cx23885_dev *dev,
+ bool enable)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_MOD,
+ enable ? CNTRL_MOD : 0);
+}
+
+static inline void control_rx_demodulation_enable(struct cx23885_dev *dev,
+ bool enable)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_DMD,
+ enable ? CNTRL_DMD : 0);
+}
+
+static inline void control_rx_s_edge_detection(struct cx23885_dev *dev,
+ u32 edge_types)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_EDG_BOTH,
+ edge_types & CNTRL_EDG_BOTH);
+}
+
+static void control_rx_s_carrier_window(struct cx23885_dev *dev,
+ unsigned int carrier,
+ unsigned int *carrier_range_low,
+ unsigned int *carrier_range_high)
+{
+ u32 v;
+ unsigned int c16 = carrier * 16;
+
+ if (*carrier_range_low < DIV_ROUND_CLOSEST(c16, 16 + 3)) {
+ v = CNTRL_WIN_3_4;
+ *carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 4);
+ } else {
+ v = CNTRL_WIN_3_3;
+ *carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 3);
+ }
+
+ if (*carrier_range_high > DIV_ROUND_CLOSEST(c16, 16 - 3)) {
+ v |= CNTRL_WIN_4_3;
+ *carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 4);
+ } else {
+ v |= CNTRL_WIN_3_3;
+ *carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 3);
+ }
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_WIN, v);
+}
+
+static inline void control_tx_polarity_invert(struct cx23885_dev *dev,
+ bool invert)
+{
+ cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_CPL,
+ invert ? CNTRL_CPL : 0);
+}
+
+/*
+ * IR Rx & Tx Clock Register helpers
+ */
+static unsigned int txclk_tx_s_carrier(struct cx23885_dev *dev,
+ unsigned int freq,
+ u16 *divider)
+{
+ *divider = carrier_freq_to_clock_divider(freq);
+ cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, *divider);
+ return clock_divider_to_carrier_freq(*divider);
+}
+
+static unsigned int rxclk_rx_s_carrier(struct cx23885_dev *dev,
+ unsigned int freq,
+ u16 *divider)
+{
+ *divider = carrier_freq_to_clock_divider(freq);
+ cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, *divider);
+ return clock_divider_to_carrier_freq(*divider);
+}
+
+static u32 txclk_tx_s_max_pulse_width(struct cx23885_dev *dev, u32 ns,
+ u16 *divider)
+{
+ u64 pulse_clocks;
+
+ if (ns > V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS)
+ ns = V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS;
+ pulse_clocks = ns_to_pulse_clocks(ns);
+ *divider = pulse_clocks_to_clock_divider(pulse_clocks);
+ cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, *divider);
+ return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
+}
+
+static u32 rxclk_rx_s_max_pulse_width(struct cx23885_dev *dev, u32 ns,
+ u16 *divider)
+{
+ u64 pulse_clocks;
+
+ if (ns > V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS)
+ ns = V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS;
+ pulse_clocks = ns_to_pulse_clocks(ns);
+ *divider = pulse_clocks_to_clock_divider(pulse_clocks);
+ cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, *divider);
+ return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
+}
+
+/*
+ * IR Tx Carrier Duty Cycle register helpers
+ */
+static unsigned int cduty_tx_s_duty_cycle(struct cx23885_dev *dev,
+ unsigned int duty_cycle)
+{
+ u32 n;
+ n = DIV_ROUND_CLOSEST(duty_cycle * 100, 625); /* 16ths of 100% */
+ if (n != 0)
+ n--;
+ if (n > 15)
+ n = 15;
+ cx23888_ir_write4(dev, CX23888_IR_CDUTY_REG, n);
+ return DIV_ROUND_CLOSEST((n+1) * 100, 16);
+}
+
+/*
+ * IR Filter Register helpers
+ */
+static u32 filter_rx_s_min_width(struct cx23885_dev *dev, u32 min_width_ns)
+{
+ u32 count = ns_to_lpf_count(min_width_ns);
+ cx23888_ir_write4(dev, CX23888_IR_FILTR_REG, count);
+ return lpf_count_to_ns(count);
+}
+
+/*
+ * IR IRQ Enable Register helpers
+ */
+static inline void irqenable_rx(struct cx23885_dev *dev, u32 mask)
+{
+ mask &= (IRQEN_RTE | IRQEN_ROE | IRQEN_RSE);
+ cx23888_ir_and_or4(dev, CX23888_IR_IRQEN_REG,
+ ~(IRQEN_RTE | IRQEN_ROE | IRQEN_RSE), mask);
+}
+
+static inline void irqenable_tx(struct cx23885_dev *dev, u32 mask)
+{
+ mask &= IRQEN_TSE;
+ cx23888_ir_and_or4(dev, CX23888_IR_IRQEN_REG, ~IRQEN_TSE, mask);
+}
+
+/*
+ * V4L2 Subdevice IR Ops
+ */
+static int cx23888_ir_irq_handler(struct v4l2_subdev *sd, u32 status,
+ bool *handled)
+{
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+
+ u32 cntrl = cx23888_ir_read4(dev, CX23888_IR_CNTRL_REG);
+ u32 irqen = cx23888_ir_read4(dev, CX23888_IR_IRQEN_REG);
+ u32 stats = cx23888_ir_read4(dev, CX23888_IR_STATS_REG);
+
+ u32 rx_data[FIFO_RX_DEPTH];
+ int i, j, k;
+ u32 events, v;
+ int tsr, rsr, rto, ror, tse, rse, rte, roe, kror;
+
+ tsr = stats & STATS_TSR; /* Tx FIFO Service Request */
+ rsr = stats & STATS_RSR; /* Rx FIFO Service Request */
+ rto = stats & STATS_RTO; /* Rx Pulse Width Timer Time Out */
+ ror = stats & STATS_ROR; /* Rx FIFO Over Run */
+
+ tse = irqen & IRQEN_TSE; /* Tx FIFO Service Request IRQ Enable */
+ rse = irqen & IRQEN_RSE; /* Rx FIFO Service Reuqest IRQ Enable */
+ rte = irqen & IRQEN_RTE; /* Rx Pulse Width Timer Time Out IRQ Enable */
+ roe = irqen & IRQEN_ROE; /* Rx FIFO Over Run IRQ Enable */
+
+ *handled = false;
+ v4l2_dbg(2, ir_888_debug, sd, "IRQ Status: %s %s %s %s %s %s\n",
+ tsr ? "tsr" : " ", rsr ? "rsr" : " ",
+ rto ? "rto" : " ", ror ? "ror" : " ",
+ stats & STATS_TBY ? "tby" : " ",
+ stats & STATS_RBY ? "rby" : " ");
+
+ v4l2_dbg(2, ir_888_debug, sd, "IRQ Enables: %s %s %s %s\n",
+ tse ? "tse" : " ", rse ? "rse" : " ",
+ rte ? "rte" : " ", roe ? "roe" : " ");
+
+ /*
+ * Transmitter interrupt service
+ */
+ if (tse && tsr) {
+ /*
+ * TODO:
+ * Check the watermark threshold setting
+ * Pull FIFO_TX_DEPTH or FIFO_TX_DEPTH/2 entries from tx_kfifo
+ * Push the data to the hardware FIFO.
+ * If there was nothing more to send in the tx_kfifo, disable
+ * the TSR IRQ and notify the v4l2_device.
+ * If there was something in the tx_kfifo, check the tx_kfifo
+ * level and notify the v4l2_device, if it is low.
+ */
+ /* For now, inhibit TSR interrupt until Tx is implemented */
+ irqenable_tx(dev, 0);
+ events = V4L2_SUBDEV_IR_TX_FIFO_SERVICE_REQ;
+ v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_TX_NOTIFY, &events);
+ *handled = true;
+ }
+
+ /*
+ * Receiver interrupt service
+ */
+ kror = 0;
+ if ((rse && rsr) || (rte && rto)) {
+ /*
+ * Receive data on RSR to clear the STATS_RSR.
+ * Receive data on RTO, since we may not have yet hit the RSR
+ * watermark when we receive the RTO.
+ */
+ for (i = 0, v = FIFO_RX_NDV;
+ (v & FIFO_RX_NDV) && !kror; i = 0) {
+ for (j = 0;
+ (v & FIFO_RX_NDV) && j < FIFO_RX_DEPTH; j++) {
+ v = cx23888_ir_read4(dev, CX23888_IR_FIFO_REG);
+ rx_data[i++] = v & ~FIFO_RX_NDV;
+ }
+ if (i == 0)
+ break;
+ j = i * sizeof(u32);
+ k = kfifo_put(state->rx_kfifo,
+ (unsigned char *) rx_data, j);
+ if (k != j)
+ kror++; /* rx_kfifo over run */
+ }
+ *handled = true;
+ }
+
+ events = 0;
+ v = 0;
+ if (kror) {
+ events |= V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN;
+ v4l2_err(sd, "IR receiver software FIFO overrun\n");
+ }
+ if (roe && ror) {
+ /*
+ * The RX FIFO Enable (CNTRL_RFE) must be toggled to clear
+ * the Rx FIFO Over Run status (STATS_ROR)
+ */
+ v |= CNTRL_RFE;
+ events |= V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN;
+ v4l2_err(sd, "IR receiver hardware FIFO overrun\n");
+ }
+ if (rte && rto) {
+ /*
+ * The IR Receiver Enable (CNTRL_RXE) must be toggled to clear
+ * the Rx Pulse Width Timer Time Out (STATS_RTO)
+ */
+ v |= CNTRL_RXE;
+ events |= V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED;
+ }
+ if (v) {
+ /* Clear STATS_ROR & STATS_RTO as needed by reseting hardware */
+ cx23888_ir_write4(dev, CX23888_IR_CNTRL_REG, cntrl & ~v);
+ cx23888_ir_write4(dev, CX23888_IR_CNTRL_REG, cntrl);
+ *handled = true;
+ }
+ if (kfifo_len(state->rx_kfifo) >= CX23888_IR_RX_KFIFO_SIZE/2)
+ events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ;
+
+ if (events)
+ v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events);
return 0;
}
-static u8 cx23888_ir_read(struct cx23885_dev *dev, u32 addr)
+/* Receiver */
+static int cx23888_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
+ ssize_t *num)
{
- u32 x = cx_read((addr & ~3));
- int shift = (addr & 3) * 8;
+ struct cx23888_ir_state *state = to_state(sd);
+ bool invert = (bool) atomic_read(&state->rx_invert);
+ u16 divider = (u16) atomic_read(&state->rxclk_divider);
+
+ unsigned int i, n;
+ u32 *p;
+ u32 u, v;
+
+ n = count / sizeof(u32) * sizeof(u32);
+ if (n == 0) {
+ *num = 0;
+ return 0;
+ }
+
+ n = kfifo_get(state->rx_kfifo, buf, n);
+
+ n /= sizeof(u32);
+ *num = n * sizeof(u32);
+
+ for (p = (u32 *) buf, i = 0; i < n; p++, i++) {
+ if ((*p & FIFO_RXTX_RTO) == FIFO_RXTX_RTO) {
+ *p = V4L2_SUBDEV_IR_PULSE_RX_SEQ_END;
+ v4l2_dbg(2, ir_888_debug, sd, "rx read: end of rx\n");
+ continue;
+ }
+
+ u = (*p & FIFO_RXTX_LVL) ? V4L2_SUBDEV_IR_PULSE_LEVEL_MASK : 0;
+ if (invert)
+ u = u ? 0 : V4L2_SUBDEV_IR_PULSE_LEVEL_MASK;
- return (x >> shift) & 0xff;
+ v = (u32) pulse_width_count_to_ns((u16) (*p & FIFO_RXTX),
+ divider);
+ if (v >= V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS)
+ v = V4L2_SUBDEV_IR_PULSE_MAX_WIDTH_NS - 1;
+
+ *p = u | v;
+
+ v4l2_dbg(2, ir_888_debug, sd, "rx read: %10u ns %s\n",
+ v, u ? "mark" : "space");
+ }
+ return 0;
}
-static inline u32 cx23888_ir_read4(struct cx23885_dev *dev, u32 addr)
+static int cx23888_ir_rx_g_parameters(struct v4l2_subdev *sd,
+ struct v4l2_subdev_ir_parameters *p)
{
- return cx_read(addr);
+ struct cx23888_ir_state *state = to_state(sd);
+ mutex_lock(&state->rx_params_lock);
+ memcpy(p, &state->rx_params, sizeof(struct v4l2_subdev_ir_parameters));
+ mutex_unlock(&state->rx_params_lock);
+ return 0;
}
-static int cx23888_ir_and_or(struct cx23885_dev *dev, u32 addr,
- unsigned and_mask, u8 or_value)
+static int cx23888_ir_rx_shutdown(struct v4l2_subdev *sd)
{
- return cx23888_ir_write(dev, addr,
- (cx23888_ir_read(dev, addr) & and_mask) |
- or_value);
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+
+ mutex_lock(&state->rx_params_lock);
+
+ /* Disable or slow down all IR Rx circuits and counters */
+ irqenable_rx(dev, 0);
+ control_rx_enable(dev, false);
+ control_rx_demodulation_enable(dev, false);
+ control_rx_s_edge_detection(dev, CNTRL_EDG_NONE);
+ filter_rx_s_min_width(dev, 0);
+ cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, RXCLK_RCD);
+
+ state->rx_params.shutdown = true;
+
+ mutex_unlock(&state->rx_params_lock);
+ return 0;
}
-static inline int cx23888_ir_and_or4(struct cx23885_dev *dev, u32 addr,
- u32 and_mask, u32 or_value)
+static int cx23888_ir_rx_s_parameters(struct v4l2_subdev *sd,
+ struct v4l2_subdev_ir_parameters *p)
{
- cx_andor(addr, and_mask, or_value);
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+ struct v4l2_subdev_ir_parameters *o = &state->rx_params;
+ u16 rxclk_divider;
+
+ if (p->shutdown)
+ return cx23888_ir_rx_shutdown(sd);
+
+ if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
+ return -ENOSYS;
+
+ mutex_lock(&state->rx_params_lock);
+
+ o->shutdown = p->shutdown;
+
+ o->mode = p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
+
+ o->bytes_per_data_element = p->bytes_per_data_element = sizeof(u32);
+
+ /* Before we tweak the hardware, we have to disable the receiver */
+ irqenable_rx(dev, 0);
+ control_rx_enable(dev, false);
+
+ control_rx_demodulation_enable(dev, p->modulation);
+ o->modulation = p->modulation;
+
+ if (p->modulation) {
+ p->carrier_freq = rxclk_rx_s_carrier(dev, p->carrier_freq,
+ &rxclk_divider);
+
+ o->carrier_freq = p->carrier_freq;
+
+ o->duty_cycle = p->duty_cycle = 50;
+
+ control_rx_s_carrier_window(dev, p->carrier_freq,
+ &p->carrier_range_lower,
+ &p->carrier_range_upper);
+ o->carrier_range_lower = p->carrier_range_lower;
+ o->carrier_range_upper = p->carrier_range_upper;
+ } else {
+ p->max_pulse_width =
+ rxclk_rx_s_max_pulse_width(dev, p->max_pulse_width,
+ &rxclk_divider);
+ o->max_pulse_width = p->max_pulse_width;
+ }
+ atomic_set(&state->rxclk_divider, rxclk_divider);
+
+ p->noise_filter_min_width =
+ filter_rx_s_min_width(dev, p->noise_filter_min_width);
+ o->noise_filter_min_width = p->noise_filter_min_width;
+
+ p->resolution = clock_divider_to_resolution(rxclk_divider);
+ o->resolution = p->resolution;
+
+ /* FIXME - make this dependent on resolution for better performance */
+ control_rx_irq_watermark(dev, RX_FIFO_HALF_FULL);
+
+ control_rx_s_edge_detection(dev, CNTRL_EDG_BOTH);
+
+ o->invert = p->invert;
+ atomic_set(&state->rx_invert, p->invert);
+
+ o->interrupt_enable = p->interrupt_enable;
+ o->enable = p->enable;
+ if (p->enable) {
+ kfifo_reset(state->rx_kfifo);
+ if (p->interrupt_enable)
+ irqenable_rx(dev, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE);
+ control_rx_enable(dev, p->enable);
+ }
+
+ mutex_unlock(&state->rx_params_lock);
+ return 0;
+}
+
+/* Transmitter */
+static int cx23888_ir_tx_write(struct v4l2_subdev *sd, u8 *buf, size_t count,
+ ssize_t *num)
+{
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+ /* For now enable the Tx FIFO Service interrupt & pretend we did work */
+ irqenable_tx(dev, IRQEN_TSE);
+ *num = count;
+ return 0;
+}
+
+static int cx23888_ir_tx_g_parameters(struct v4l2_subdev *sd,
+ struct v4l2_subdev_ir_parameters *p)
+{
+ struct cx23888_ir_state *state = to_state(sd);
+ mutex_lock(&state->tx_params_lock);
+ memcpy(p, &state->tx_params, sizeof(struct v4l2_subdev_ir_parameters));
+ mutex_unlock(&state->tx_params_lock);
return 0;
}
+static int cx23888_ir_tx_shutdown(struct v4l2_subdev *sd)
+{
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+
+ mutex_lock(&state->tx_params_lock);
+
+ /* Disable or slow down all IR Tx circuits and counters */
+ irqenable_tx(dev, 0);
+ control_tx_enable(dev, false);
+ control_tx_modulation_enable(dev, false);
+ cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, TXCLK_TCD);
+
+ state->tx_params.shutdown = true;
+
+ mutex_unlock(&state->tx_params_lock);
+ return 0;
+}
+
+static int cx23888_ir_tx_s_parameters(struct v4l2_subdev *sd,
+ struct v4l2_subdev_ir_parameters *p)
+{
+ struct cx23888_ir_state *state = to_state(sd);
+ struct cx23885_dev *dev = state->dev;
+ struct v4l2_subdev_ir_parameters *o = &state->tx_params;
+ u16 txclk_divider;
+
+ if (p->shutdown)
+ return cx23888_ir_tx_shutdown(sd);
+
+ if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
+ return -ENOSYS;
+
+ mutex_lock(&state->tx_params_lock);
+
+ o->shutdown = p->shutdown;
+
+ o->mode = p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
+
+ o->bytes_per_data_element = p->bytes_per_data_element = sizeof(u32);
+
+ /* Before we tweak the hardware, we have to disable the transmitter */
+ irqenable_tx(dev, 0);
+ control_tx_enable(dev, false);
+
+ control_tx_modulation_enable(dev, p->modulation);
+ o->modulation = p->modulation;
+
+ if (p->modulation) {
+ p->carrier_freq = txclk_tx_s_carrier(dev, p->carrier_freq,
+ &txclk_divider);
+ o->carrier_freq = p->carrier_freq;
+
+ p->duty_cycle = cduty_tx_s_duty_cycle(dev, p->duty_cycle);
+ o->duty_cycle = p->duty_cycle;
+ } else {
+ p->max_pulse_width =
+ txclk_tx_s_max_pulse_width(dev, p->max_pulse_width,
+ &txclk_divider);
+ o->max_pulse_width = p->max_pulse_width;
+ }
+ atomic_set(&state->txclk_divider, txclk_divider);
+
+ p->resolution = clock_divider_to_resolution(txclk_divider);
+ o->resolution = p->resolution;
+
+ /* FIXME - make this dependent on resolution for better performance */
+ control_tx_irq_watermark(dev, TX_FIFO_HALF_EMPTY);
+
+ control_tx_polarity_invert(dev, p->invert);
+ o->invert = p->invert;
+
+ o->interrupt_enable = p->interrupt_enable;
+ o->enable = p->enable;
+ if (p->enable) {
+ kfifo_reset(state->tx_kfifo);
+ if (p->interrupt_enable)
+ irqenable_tx(dev, IRQEN_TSE);
+ control_tx_enable(dev, p->enable);
+ }
+
+ mutex_unlock(&state->tx_params_lock);
+ return 0;
+}
+
+
+/*
+ * V4L2 Subdevice Core Ops
+ */
static int cx23888_ir_log_status(struct v4l2_subdev *sd)
{
struct cx23888_ir_state *state = to_state(sd);
struct cx23885_dev *dev = state->dev;
- u8 cntrl = cx23888_ir_read(dev, CX23888_IR_CNTRL_REG+1);
- v4l2_info(sd, "receiver %sabled\n", cntrl & 0x1 ? "en" : "dis");
- v4l2_info(sd, "transmitter %sabled\n", cntrl & 0x2 ? "en" : "dis");
+ char *s;
+ int i, j;
+
+ u32 cntrl = cx23888_ir_read4(dev, CX23888_IR_CNTRL_REG);
+ u32 txclk = cx23888_ir_read4(dev, CX23888_IR_TXCLK_REG) & TXCLK_TCD;
+ u32 rxclk = cx23888_ir_read4(dev, CX23888_IR_RXCLK_REG) & RXCLK_RCD;
+ u32 cduty = cx23888_ir_read4(dev, CX23888_IR_CDUTY_REG) & CDUTY_CDC;
+ u32 stats = cx23888_ir_read4(dev, CX23888_IR_STATS_REG);
+ u32 irqen = cx23888_ir_read4(dev, CX23888_IR_IRQEN_REG);
+ u32 filtr = cx23888_ir_read4(dev, CX23888_IR_FILTR_REG) & FILTR_LPF;
+
+ v4l2_info(sd, "IR Receiver:\n");
+ v4l2_info(sd, "\tEnabled: %s\n",
+ cntrl & CNTRL_RXE ? "yes" : "no");
+ v4l2_info(sd, "\tDemodulation from a carrier: %s\n",
+ cntrl & CNTRL_DMD ? "enabled" : "disabled");
+ v4l2_info(sd, "\tFIFO: %s\n",
+ cntrl & CNTRL_RFE ? "enabled" : "disabled");
+ switch (cntrl & CNTRL_EDG) {
+ case CNTRL_EDG_NONE:
+ s = "disabled";
+ break;
+ case CNTRL_EDG_FALL:
+ s = "falling edge";
+ break;
+ case CNTRL_EDG_RISE:
+ s = "rising edge";
+ break;
+ case CNTRL_EDG_BOTH:
+ s = "rising & falling edges";
+ break;
+ default:
+ s = "??? edge";
+ break;
+ }
+ v4l2_info(sd, "\tPulse timers' start/stop trigger: %s\n", s);
+ v4l2_info(sd, "\tFIFO data on pulse timer overflow: %s\n",
+ cntrl & CNTRL_R ? "not loaded" : "overflow marker");
+ v4l2_info(sd, "\tFIFO interrupt watermark: %s\n",
+ cntrl & CNTRL_RIC ? "not empty" : "half full or greater");
+ v4l2_info(sd, "\tLoopback mode: %s\n",
+ cntrl & CNTRL_LBM ? "loopback active" : "normal receive");
+ if (cntrl & CNTRL_DMD) {
+ v4l2_info(sd, "\tExpected carrier (16 clocks): %u Hz\n",
+ clock_divider_to_carrier_freq(rxclk));
+ switch (cntrl & CNTRL_WIN) {
+ case CNTRL_WIN_3_3:
+ i = 3;
+ j = 3;
+ break;
+ case CNTRL_WIN_4_3:
+ i = 4;
+ j = 3;
+ break;
+ case CNTRL_WIN_3_4:
+ i = 3;
+ j = 4;
+ break;
+ case CNTRL_WIN_4_4:
+ i = 4;
+ j = 4;
+ break;
+ default:
+ i = 0;
+ j = 0;
+ break;
+ }
+ v4l2_info(sd, "\tNext carrier edge window: 16 clocks "
+ "-%1d/+%1d, %u to %u Hz\n", i, j,
+ clock_divider_to_freq(rxclk, 16 + j),
+ clock_divider_to_freq(rxclk, 16 - i));
+ } else {
+ v4l2_info(sd, "\tMax measurable pulse width: %u us, "
+ "%llu ns\n",
+ pulse_width_count_to_us(FIFO_RXTX, rxclk),
+ pulse_width_count_to_ns(FIFO_RXTX, rxclk));
+ }
+ v4l2_info(sd, "\tLow pass filter: %s\n",
+ filtr ? "enabled" : "disabled");
+ if (filtr)
+ v4l2_info(sd, "\tMin acceptable pulse width (LPF): %u us, "
+ "%u ns\n",
+ lpf_count_to_us(filtr),
+ lpf_count_to_ns(filtr));
+ v4l2_info(sd, "\tPulse width timer timed-out: %s\n",
+ stats & STATS_RTO ? "yes" : "no");
+ v4l2_info(sd, "\tPulse width timer time-out intr: %s\n",
+ irqen & IRQEN_RTE ? "enabled" : "disabled");
+ v4l2_info(sd, "\tFIFO overrun: %s\n",
+ stats & STATS_ROR ? "yes" : "no");
+ v4l2_info(sd, "\tFIFO overrun interrupt: %s\n",
+ irqen & IRQEN_ROE ? "enabled" : "disabled");
+ v4l2_info(sd, "\tBusy: %s\n",
+ stats & STATS_RBY ? "yes" : "no");
+ v4l2_info(sd, "\tFIFO service requested: %s\n",
+ stats & STATS_RSR ? "yes" : "no");
+ v4l2_info(sd, "\tFIFO service request interrupt: %s\n",
+ irqen & IRQEN_RSE ? "enabled" : "disabled");
+
+ v4l2_info(sd, "IR Transmitter:\n");
+ v4l2_info(sd, "\tEnabled: %s\n",
+ cntrl & CNTRL_TXE ? "yes" : "no");
+ v4l2_info(sd, "\tModulation onto a carrier: %s\n",
+ cntrl & CNTRL_MOD ? "enabled" : "disabled");
+ v4l2_info(sd, "\tFIFO: %s\n",
+ cntrl & CNTRL_TFE ? "enabled" : "disabled");
+ v4l2_info(sd, "\tFIFO interrupt watermark: %s\n",
+ cntrl & CNTRL_TIC ? "not empty" : "half full or less");
+ v4l2_info(sd, "\tSignal polarity: %s\n",
+ cntrl & CNTRL_CPL ? "0:mark 1:space" : "0:space 1:mark");
+ if (cntrl & CNTRL_MOD) {
+ v4l2_info(sd, "\tCarrier (16 clocks): %u Hz\n",
+ clock_divider_to_carrier_freq(txclk));
+ v4l2_info(sd, "\tCarrier duty cycle: %2u/16\n",
+ cduty + 1);
+ } else {
+ v4l2_info(sd, "\tMax pulse width: %u us, "
+ "%llu ns\n",
+ pulse_width_count_to_us(FIFO_RXTX, txclk),
+ pulse_width_count_to_ns(FIFO_RXTX, txclk));
+ }
+ v4l2_info(sd, "\tBusy: %s\n",
+ stats & STATS_TBY ? "yes" : "no");
+ v4l2_info(sd, "\tFIFO service requested: %s\n",
+ stats & STATS_TSR ? "yes" : "no");
+ v4l2_info(sd, "\tFIFO service request interrupt: %s\n",
+ irqen & IRQEN_TSE ? "enabled" : "disabled");
+
return 0;
}
@@ -187,19 +1105,81 @@ static const struct v4l2_subdev_core_ops cx23888_ir_core_ops = {
#endif
};
+static const struct v4l2_subdev_ir_ops cx23888_ir_ir_ops = {
+ .interrupt_service_routine = cx23888_ir_irq_handler,
+
+ .rx_read = cx23888_ir_rx_read,
+ .rx_g_parameters = cx23888_ir_rx_g_parameters,
+ .rx_s_parameters = cx23888_ir_rx_s_parameters,
+
+ .tx_write = cx23888_ir_tx_write,
+ .tx_g_parameters = cx23888_ir_tx_g_parameters,
+ .tx_s_parameters = cx23888_ir_tx_s_parameters,
+};
+
static const struct v4l2_subdev_ops cx23888_ir_controller_ops = {
.core = &cx23888_ir_core_ops,
+ .ir = &cx23888_ir_ir_ops,
+};
+
+static const struct v4l2_subdev_ir_parameters default_rx_params = {
+ .bytes_per_data_element = sizeof(u32),
+ .mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
+
+ .enable = false,
+ .interrupt_enable = false,
+ .shutdown = true,
+
+ .modulation = true,
+ .carrier_freq = 36000, /* 36 kHz - RC-5, RC-6, and RC-6A carrier */
+
+ /* RC-5: 666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
+ /* RC-6A: 333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
+ .noise_filter_min_width = 333333, /* ns */
+ .carrier_range_lower = 35000,
+ .carrier_range_upper = 37000,
+ .invert = false,
+};
+
+static const struct v4l2_subdev_ir_parameters default_tx_params = {
+ .bytes_per_data_element = sizeof(u32),
+ .mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
+
+ .enable = false,
+ .interrupt_enable = false,
+ .shutdown = true,
+
+ .modulation = true,
+ .carrier_freq = 36000, /* 36 kHz - RC-5 carrier */
+ .duty_cycle = 25, /* 25 % - RC-5 carrier */
+ .invert = false,
};
int cx23888_ir_probe(struct cx23885_dev *dev)
{
struct cx23888_ir_state *state;
struct v4l2_subdev *sd;
+ struct v4l2_subdev_ir_parameters default_params;
+ int ret;
state = kzalloc(sizeof(struct cx23888_ir_state), GFP_KERNEL);
if (state == NULL)
return -ENOMEM;
+ spin_lock_init(&state->rx_kfifo_lock);
+ state->rx_kfifo = kfifo_alloc(CX23888_IR_RX_KFIFO_SIZE, GFP_KERNEL,
+ &state->rx_kfifo_lock);
+ if (state->rx_kfifo == NULL)
+ return -ENOMEM;
+
+ spin_lock_init(&state->tx_kfifo_lock);
+ state->tx_kfifo = kfifo_alloc(CX23888_IR_TX_KFIFO_SIZE, GFP_KERNEL,
+ &state->tx_kfifo_lock);
+ if (state->tx_kfifo == NULL) {
+ kfifo_free(state->rx_kfifo);
+ return -ENOMEM;
+ }
+
state->dev = dev;
state->id = V4L2_IDENT_CX23888_IR;
state->rev = 0;
@@ -210,7 +1190,30 @@ int cx23888_ir_probe(struct cx23885_dev *dev)
/* FIXME - fix the formatting of dev->v4l2_dev.name and use it */
snprintf(sd->name, sizeof(sd->name), "%s/888-ir", dev->name);
sd->grp_id = CX23885_HW_888_IR;
- return v4l2_device_register_subdev(&dev->v4l2_dev, sd);
+
+ ret = v4l2_device_register_subdev(&dev->v4l2_dev, sd);
+ if (ret == 0) {
+ /*
+ * Ensure no interrupts arrive from '888 specific conditions,
+ * since we ignore them in this driver to have commonality with
+ * similar IR controller cores.
+ */
+ cx23888_ir_write4(dev, CX23888_IR_IRQEN_REG, 0);
+
+ mutex_init(&state->rx_params_lock);
+ memcpy(&default_params, &default_rx_params,
+ sizeof(struct v4l2_subdev_ir_parameters));
+ v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
+
+ mutex_init(&state->tx_params_lock);
+ memcpy(&default_params, &default_tx_params,
+ sizeof(struct v4l2_subdev_ir_parameters));
+ v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
+ } else {
+ kfifo_free(state->rx_kfifo);
+ kfifo_free(state->tx_kfifo);
+ }
+ return ret;
}
int cx23888_ir_remove(struct cx23885_dev *dev)
@@ -222,11 +1225,13 @@ int cx23888_ir_remove(struct cx23885_dev *dev)
if (sd == NULL)
return -ENODEV;
- /* Disable receiver and transmitter */
- cx23888_ir_and_or(dev, CX23888_IR_CNTRL_REG+1, 0xfc, 0);
+ cx23888_ir_rx_shutdown(sd);
+ cx23888_ir_tx_shutdown(sd);
state = to_state(sd);
v4l2_device_unregister_subdev(sd);
+ kfifo_free(state->rx_kfifo);
+ kfifo_free(state->tx_kfifo);
kfree(state);
/* Nothing more to free() as state held the actual v4l2_subdev object */
return 0;