altos/stm: Note that ao_i2c_recv_dma_isr isn't actually used
[fw/altos] / src / stm / ao_i2c_stm.c
index 4d7d8d87a37fff150c6418f7f328060504bf0305..c02bc5a535169f0922b638f4947756c8d5133256 100644 (file)
@@ -3,7 +3,8 @@
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License.
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -23,6 +24,8 @@ struct ao_i2c_stm_info {
        struct stm_i2c  *stm_i2c;
 };
 
+#define I2C_FAST       1
+
 #define I2C_TIMEOUT    100
 
 #define I2C_IDLE       0
@@ -33,6 +36,33 @@ static uint8_t       ao_i2c_state[STM_NUM_I2C];
 static uint16_t        ao_i2c_addr[STM_NUM_I2C];
 uint8_t        ao_i2c_mutex[STM_NUM_I2C];
 
+# define I2C_HIGH_SLOW 5000    /* ns, 100kHz clock */
+#ifdef TELEMEGA
+# define I2C_HIGH_FAST 2000    /* ns, 167kHz clock */
+#else
+# define I2C_HIGH_FAST 1000    /* ns, 333kHz clock */
+#endif
+
+# define I2C_RISE_SLOW 500     /* ns */
+# define I2C_RISE_FAST 100     /* ns */
+
+/* Clock period in ns */
+#define CYCLES(period) (((period) * (AO_PCLK1 / 1000)) / 1000000)
+
+#define max(a,b)       ((a) > (b) ? (a) : (b))
+#define I2C_CCR_HIGH_SLOW      max(4,CYCLES(I2C_HIGH_SLOW))
+#define I2C_CCR_HIGH_FAST      max(4,CYCLES(I2C_HIGH_FAST))
+#define I2C_TRISE_SLOW         (CYCLES(I2C_RISE_SLOW) + 1)
+#define I2C_TRISE_FAST         (CYCLES(I2C_RISE_FAST) + 1)
+
+#if I2C_FAST
+#define I2C_TRISE      I2C_TRISE_FAST
+#define I2C_CCR_HIGH   I2C_CCR_HIGH_FAST
+#else
+#define I2C_TRISE      I2C_TRISE_SLOW
+#define I2C_CCR_HIGH   I2C_CCR_HIGH_SLOW
+#endif
+
 #if AO_PCLK1 == 2000000
 # define AO_STM_I2C_CR2_FREQ   STM_I2C_CR2_FREQ_2_MHZ
 #endif
@@ -45,6 +75,9 @@ uint8_t       ao_i2c_mutex[STM_NUM_I2C];
 #if AO_PCLK1 == 16000000
 # define AO_STM_I2C_CR2_FREQ   STM_I2C_CR2_FREQ_16_MHZ
 #endif
+#if AO_PCLK1 == 24000000
+# define AO_STM_I2C_CR2_FREQ   STM_I2C_CR2_FREQ_24_MHZ
+#endif
 #if AO_PCLK1 == 32000000
 # define AO_STM_I2C_CR2_FREQ   STM_I2C_CR2_FREQ_32_MHZ
 #endif
@@ -108,7 +141,7 @@ ao_i2c_ev_isr(uint8_t index)
                ao_wakeup(&ao_i2c_state[index]);
        }
        if (sr1 & (1 << STM_I2C_SR1_RXNE)) {
-               if (ao_i2c_recv_len[index]) {                   
+               if (ao_i2c_recv_len[index]) {
                        *(ao_i2c_recv_data[index]++) = stm_i2c->dr;
                        if (!--ao_i2c_recv_len[index])
                                ao_wakeup(&ao_i2c_recv_len[index]);
@@ -156,7 +189,6 @@ uint8_t
 ao_i2c_start(uint8_t index, uint16_t addr)
 {
        struct stm_i2c  *stm_i2c = ao_i2c_stm_info[index].stm_i2c;
-       uint32_t        sr1, sr2;
        int             t;
 
        ao_i2c_state[index] = I2C_IDLE;
@@ -167,14 +199,13 @@ ao_i2c_start(uint8_t index, uint16_t addr)
                if (!(stm_i2c->cr1 & (1 << STM_I2C_CR1_START)))
                        break;
        }
+       ao_arch_block_interrupts();
        stm_i2c->cr2 = AO_STM_I2C_CR2 | (1 << STM_I2C_CR2_ITEVTEN) | (1 << STM_I2C_CR2_ITERREN);
-       ao_alarm(AO_MS_TO_TICKS(250));
-       cli();
+       ao_i2c_ev_isr(index);
        while (ao_i2c_state[index] == I2C_IDLE)
-               if (ao_sleep(&ao_i2c_state[index]))
+               if (ao_sleep_for(&ao_i2c_state[index], AO_MS_TO_TICKS(250)))
                        break;
-       sei();
-       ao_clear_alarm();
+       ao_arch_release_interrupts();
        return ao_i2c_state[index] == I2C_RUNNING;
 }
 
@@ -192,16 +223,28 @@ ao_i2c_wait_stop(uint8_t index)
        ao_i2c_state[index] = I2C_IDLE;
 }
 
+static void
+ao_i2c_wait_addr(uint8_t index)
+{
+       struct stm_i2c  *stm_i2c = ao_i2c_stm_info[index].stm_i2c;
+       int     t;
+
+       for (t = 0; t < I2C_TIMEOUT; t++)
+               if (!(stm_i2c->sr1 & (1 << STM_I2C_SR1_ADDR)))
+                       break;
+       if (t)
+               printf ("wait_addr %d\n", t);
+}
+
 uint8_t
 ao_i2c_send(void *block, uint16_t len, uint8_t index, uint8_t stop)
 {
        struct stm_i2c  *stm_i2c = ao_i2c_stm_info[index].stm_i2c;
-       uint8_t         *b = block;
-       uint32_t        sr1;
        uint8_t         tx_dma_index = ao_i2c_stm_info[index].tx_dma_index;
 
        /* Clear any pending ADDR bit */
        (void) stm_i2c->sr2;
+       ao_i2c_wait_addr(index);
        stm_i2c->cr2 = AO_STM_I2C_CR2 | (1 << STM_I2C_CR2_DMAEN);
        ao_dma_set_transfer(tx_dma_index,
                            &stm_i2c->dr,
@@ -215,26 +258,24 @@ ao_i2c_send(void *block, uint16_t len, uint8_t index, uint8_t stop)
                            (0 << STM_DMA_CCR_PINC) |
                            (0 << STM_DMA_CCR_CIRC) |
                            (STM_DMA_CCR_DIR_MEM_TO_PER << STM_DMA_CCR_DIR));
-                          
+
        ao_dma_start(tx_dma_index);
-       ao_alarm(1 + len);
-       cli();
+       ao_arch_block_interrupts();
        while (!ao_dma_done[tx_dma_index])
-               if (ao_sleep(&ao_dma_done[tx_dma_index]))
+               if (ao_sleep_for(&ao_dma_done[tx_dma_index], 1 + len))
                        break;
-       ao_clear_alarm();
        ao_dma_done_transfer(tx_dma_index);
        stm_i2c->cr2 = AO_STM_I2C_CR2 | (1 << STM_I2C_CR2_ITEVTEN) | (1 << STM_I2C_CR2_ITERREN);
        while ((stm_i2c->sr1 & (1 << STM_I2C_SR1_BTF)) == 0)
-               if (ao_sleep(&ao_i2c_state[index]))
+               if (ao_sleep_for(&ao_i2c_state[index], 1 + len))
                        break;
        stm_i2c->cr2 = AO_STM_I2C_CR2;
-       sei();
+       ao_arch_release_interrupts();
        if (stop) {
                stm_i2c->cr1 = AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP);
                ao_i2c_wait_stop(index);
        }
-       return TRUE;
+       return true;
 }
 
 void
@@ -259,12 +300,10 @@ uint8_t
 ao_i2c_recv(void *block, uint16_t len, uint8_t index, uint8_t stop)
 {
        struct stm_i2c  *stm_i2c = ao_i2c_stm_info[index].stm_i2c;
-       uint8_t         *b = block;
-       int             t;
-       uint8_t         ret = TRUE;
+       uint8_t         ret = true;
 
        if (len == 0)
-               return TRUE;
+               return true;
        if (len == 1) {
                ao_i2c_recv_data[index] = block;
                ao_i2c_recv_len[index] = 1;
@@ -272,6 +311,7 @@ ao_i2c_recv(void *block, uint16_t len, uint8_t index, uint8_t stop)
 
                /* Clear any pending ADDR bit */
                stm_i2c->sr2;
+               ao_i2c_wait_addr(index);
 
                /* Enable interrupts to transfer the byte */
                stm_i2c->cr2 = (AO_STM_I2C_CR2 |
@@ -281,14 +321,12 @@ ao_i2c_recv(void *block, uint16_t len, uint8_t index, uint8_t stop)
                if (stop)
                        stm_i2c->cr1 = AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP);
 
-               ao_alarm(1);
-               cli();
+               ao_arch_block_interrupts();
                while (ao_i2c_recv_len[index])
-                       if (ao_sleep(&ao_i2c_recv_len[index]))
+                       if (ao_sleep_for(&ao_i2c_recv_len[index], 1))
                                break;
-               sei();
+               ao_arch_release_interrupts();
                ret = ao_i2c_recv_len[index] == 0;
-               ao_clear_alarm();
        } else {
                uint8_t         rx_dma_index = ao_i2c_stm_info[index].rx_dma_index;
                ao_dma_set_transfer(rx_dma_index,
@@ -296,27 +334,37 @@ ao_i2c_recv(void *block, uint16_t len, uint8_t index, uint8_t stop)
                                    block,
                                    len,
                                    (0 << STM_DMA_CCR_MEM2MEM) |
-                                   (STM_DMA_CCR_PL_MEDIUM << STM_DMA_CCR_PL) |
+                                   (STM_DMA_CCR_PL_HIGH << STM_DMA_CCR_PL) |
                                    (STM_DMA_CCR_MSIZE_8 << STM_DMA_CCR_MSIZE) |
                                    (STM_DMA_CCR_PSIZE_8 << STM_DMA_CCR_PSIZE) |
                                    (1 << STM_DMA_CCR_MINC) |
                                    (0 << STM_DMA_CCR_PINC) |
                                    (0 << STM_DMA_CCR_CIRC) |
                                    (STM_DMA_CCR_DIR_PER_TO_MEM << STM_DMA_CCR_DIR));
+
+               /* XXX ao_i2c_recv_dma_isr hasn't ever been used, so it
+                * doesn't appear to be necessary. Testing with a device
+                * that uses i2c would really be useful here to discover
+                * whether this function is necessary or not.
+                */
+#if 0
+               ao_dma_set_isr(rx_dma_index, ao_i2c_recv_dma_isr);
+#else
+               (void) ao_i2c_recv_dma_isr;
+#endif
                stm_i2c->cr1 = AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_ACK);
                stm_i2c->cr2 = AO_STM_I2C_CR2 |
                        (1 << STM_I2C_CR2_DMAEN) | (1 << STM_I2C_CR2_LAST);
                /* Clear any pending ADDR bit */
                (void) stm_i2c->sr2;
+               ao_i2c_wait_addr(index);
 
                ao_dma_start(rx_dma_index);
-               ao_alarm(len);
-               cli();
+               ao_arch_block_interrupts();
                while (!ao_dma_done[rx_dma_index])
-                       if (ao_sleep(&ao_dma_done[rx_dma_index]))
+                       if (ao_sleep_for(&ao_dma_done[rx_dma_index], len))
                                break;
-               sei();
-               ao_clear_alarm();
+               ao_arch_release_interrupts();
                ret = ao_dma_done[rx_dma_index];
                ao_dma_done_transfer(rx_dma_index);
                stm_i2c->cr1 = AO_STM_I2C_CR1 | (1 << STM_I2C_CR1_STOP);
@@ -346,14 +394,23 @@ ao_i2c_channel_init(uint8_t index)
        stm_i2c->sr1 = 0;
        stm_i2c->sr2 = 0;
 
-       stm_i2c->ccr = ((1 << STM_I2C_CCR_FS) |
+       stm_i2c->ccr = ((I2C_FAST << STM_I2C_CCR_FS) |
                        (0 << STM_I2C_CCR_DUTY) |
-                       (20 << STM_I2C_CCR_CCR));
-       
+                       (I2C_CCR_HIGH << STM_I2C_CCR_CCR));
+
+       stm_i2c->trise = I2C_TRISE;
 
        stm_i2c->cr1 = AO_STM_I2C_CR1;
 }
 
+static inline void
+i2c_pin_set(struct stm_gpio *gpio, int pin)
+{
+       stm_afr_set(gpio, pin, STM_AFR_AF4);
+       stm_ospeedr_set(gpio, pin, STM_OSPEEDR_400kHz);
+       stm_pupdr_set(gpio, pin, STM_PUPDR_PULL_UP);
+}
+
 void
 ao_i2c_init(void)
 {
@@ -361,12 +418,12 @@ ao_i2c_init(void)
        stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOBEN);
 #if HAS_I2C_1
 # if I2C_1_PB6_PB7
-       stm_afr_set(&stm_gpiob, 6, STM_AFR_AF4);
-       stm_afr_set(&stm_gpiob, 7, STM_AFR_AF4);
+       i2c_pin_set(&stm_gpiob, 6);
+       i2c_pin_set(&stm_gpiob, 7);
 # else
 #  if I2C_1_PB8_PB9
-       stm_afr_set(&stm_gpiob, 8, STM_AFR_AF4);
-       stm_afr_set(&stm_gpiob, 9, STM_AFR_AF4);
+       i2c_pin_set(&stm_gpiob, 8);
+       i2c_pin_set(&stm_gpiob, 9);
 #  else
 #   error "No I2C_1 port configuration specified"
 #  endif
@@ -376,15 +433,15 @@ ao_i2c_init(void)
        ao_i2c_channel_init(0);
 
        stm_nvic_set_enable(STM_ISR_I2C1_EV_POS);
-       stm_nvic_set_priority(STM_ISR_I2C1_EV_POS, 3);
+       stm_nvic_set_priority(STM_ISR_I2C1_EV_POS, AO_STM_NVIC_MED_PRIORITY);
        stm_nvic_set_enable(STM_ISR_I2C1_ER_POS);
-       stm_nvic_set_priority(STM_ISR_I2C1_ER_POS, 3);
+       stm_nvic_set_priority(STM_ISR_I2C1_ER_POS, AO_STM_NVIC_MED_PRIORITY);
 #endif
 
 #if HAS_I2C_2
 # if I2C_2_PB10_PB11
-       stm_afr_set(&stm_gpiob, 10, STM_AFR_AF4);
-       stm_afr_set(&stm_gpiob, 11, STM_AFR_AF4);
+       i2c_pin_set(&stm_gpiob, 10);
+       i2c_pin_set(&stm_gpiob, 11);
 # else
 #  error "No I2C_2 port configuration specified"
 # endif
@@ -392,8 +449,8 @@ ao_i2c_init(void)
        ao_i2c_channel_init(1);
 
        stm_nvic_set_enable(STM_ISR_I2C2_EV_POS);
-       stm_nvic_set_priority(STM_ISR_I2C2_EV_POS, 3);
+       stm_nvic_set_priority(STM_ISR_I2C2_EV_POS, AO_STM_NVIC_MED_PRIORITY);
        stm_nvic_set_enable(STM_ISR_I2C2_ER_POS);
-       stm_nvic_set_priority(STM_ISR_I2C2_ER_POS, 3);
+       stm_nvic_set_priority(STM_ISR_I2C2_ER_POS, AO_STM_NVIC_MED_PRIORITY);
 #endif
 }