2 * Copyright © 2013 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
20 static uint8_t ao_spi_mutex[LPC_NUM_SPI];
22 static struct lpc_ssp * const ao_lpc_ssp[LPC_NUM_SPI] = { &lpc_ssp0, &lpc_ssp1 };
24 static uint8_t spi_dev_null;
26 #define spi_loop(len, put, get) do { \
28 /* Wait for space in the fifo */ \
29 while ((lpc_ssp->sr & (1 << LPC_SSP_SR_TNF)) == 0) \
38 /* Wait for the fifo to drain */ \
39 while ((lpc_ssp->sr & (1 << LPC_SSP_SR_BSY))) \
44 ao_spi_send(void *block, uint16_t len, uint8_t id)
47 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
49 spi_loop(len, *b++, (void));
53 ao_spi_send_fixed(uint8_t value, uint16_t len, uint8_t id)
55 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
57 spi_loop(len, value, (void));
61 ao_spi_recv(void *block, uint16_t len, uint8_t id)
64 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
66 spi_loop(len, 0xff, *b++ =);
70 ao_spi_duplex(void *out, void *in, uint16_t len, uint8_t id)
74 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
76 spi_loop(len, *o++, *i++ =);
80 ao_spi_get(uint8_t id, uint32_t speed)
82 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
84 ao_mutex_get(&ao_spi_mutex[id]);
86 /* Set the clock prescale */
87 lpc_ssp->cpsr = speed;
89 /* Enable the device */
90 lpc_ssp->cr1 = ((0 << LPC_SSP_CR1_LBM) |
91 (1 << LPC_SSP_CR1_SSE) |
92 (LPC_SSP_CR1_MS_MASTER << LPC_SSP_CR1_MS) |
93 (0 << LPC_SSP_CR1_SOD));
97 ao_spi_put(uint8_t id)
99 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
101 /* Disable the device */
102 lpc_ssp->cr1 = ((0 << LPC_SSP_CR1_LBM) |
103 (0 << LPC_SSP_CR1_SSE) |
104 (LPC_SSP_CR1_MS_MASTER << LPC_SSP_CR1_MS) |
105 (0 << LPC_SSP_CR1_SOD));
106 ao_mutex_put(&ao_spi_mutex[id]);
110 ao_spi_channel_init(uint8_t id)
112 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
115 lpc_ssp->cr0 = ((LPC_SSP_CR0_DSS_8 << LPC_SSP_CR0_DSS) |
116 (LPC_SSP_CR0_FRF_SPI << LPC_SSP_CR0_FRF) |
117 (0 << LPC_SSP_CR0_CPOL) |
118 (0 << LPC_SSP_CR0_CPHA) |
119 (0 << LPC_SSP_CR0_SCR));
120 /* Drain the receive fifo */
121 for (d = 0; d < LPC_SSP_FIFOSIZE; d++)
130 lpc_ioconf.pio0_6 = ao_lpc_alternate(LPC_IOCONF_FUNC_SCK0);
131 lpc_ioconf.pio0_8 = ao_lpc_alternate(LPC_IOCONF_FUNC_MISO0);
132 lpc_ioconf.pio0_9 = ao_lpc_alternate(LPC_IOCONF_FUNC_MOSI0);
134 /* Enable the device */
135 lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_SSP0);
137 /* Turn on the clock */
138 lpc_scb.ssp0clkdiv = 1;
140 /* Reset the device */
141 lpc_scb.presetctrl &= ~(1 << LPC_SCB_PRESETCTRL_SSP0_RST_N);
142 lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP0_RST_N);
143 ao_spi_channel_init(0);
149 lpc_ioconf.pio1_15 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_15_SCK1);
153 lpc_ioconf.pio1_20 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_20_SCK1);
157 #error "No pin specified for SCK1"
161 lpc_ioconf.pio0_22 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_22_MISO1);
165 lpc_ioconf.pio1_21 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_21_MISO1);
169 #error "No pin specified for MISO1"
173 lpc_ioconf.pio1_21 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_21_MOSI1);
177 lpc_ioconf.pio1_22 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_22_MOSI1);
181 #error "No pin specified for MOSI1"
184 /* Enable the device */
185 lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_SSP1);
187 /* Turn on the clock */
188 lpc_scb.ssp1clkdiv = 1;
190 /* De-assert reset */
191 lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP1_RST_N);
192 ao_spi_channel_init(1);
193 #endif /* HAS_SPI_1 */