es58x_alloc_urb(9)

💖 es58x_alloc_urb(9) 💖

okay bestie, welcome to the es58x_alloc_urb page — it's a Kernel API Manual moment, and yes we're reading kernel API docs together, this is our life now 🎀

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✨ NAME ✨

es58x_alloc_urb — allocate memory for an URB and its transfer buffer. two-for-one slay 💅

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🌸 SYNOPSIS 🌸

int es58x_alloc_urb (struct es58x_device *es58x_dev , struct urb **urb ,
u8 **buf , size_t buf_len , gfp_t mem_flags );

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🦋 ARGUMENTS 🦋

• es58x_dev — the ES58X device itself. the main character of this whole operation 👑
• urb — the URB that's gonna get allocated. that's the whole point, lowkey.
• buf — this one's used to return the DMA address of the buffer. it's a return channel disguised as an argument, iconic behavior tbh ✨
• buf_len — the buffer size you're requesting. how much room do we need, bestie?
• mem_flags — these affect whether the allocation is allowed to block. like, can it chill and wait, or nah? 😴

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💜 DESCRIPTION 💜

So what does it actually do? It allocates an URB and its transfer_buffer, and then it sets the transfer_dma address. all three, one function, no cap 🫶

Where do we use it? Two places, fr fr:

• at start-up, to allocate all the RX URBs at once (bulk girlie behavior, we love efficiency)
• during run time, for TX URBs

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🔥 RETURN 🔥

• zero on success — we love a win 🎉
• -ENOMEM if no memory is available — 😭 the allocation said no

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💀 SEE ALSO 💀

The kernel file lives at ./drivers/net/can/usb/etas_es58x/es58x_core.c — go peek, iykyk 👀

And here's the whole friend group, everyone's invited to the group chat:

• es58x_calculate_crc(9) — es58x_get_crc(9) — es58x_set_crc(9) — es58x_check_crc(9)
• es58x_timestamp_to_ns(9) — es58x_set_skb_timestamp(9) — es58x_rx_timestamp(9)
• es58x_set_realtime_diff_ns(9)
• es58x_is_can_state_active(9) — es58x_is_echo_skb_threshold_reached(9)
• es58x_can_free_echo_skb_tail(9) — es58x_can_get_echo_skb_recovery(9) — es58x_can_get_echo_skb(9) — es58x_can_reset_echo_fifo(9)
• es58x_flush_pending_tx_msg(9) — es58x_tx_ack_msg(9)
• es58x_rx_can_msg(9) — es58x_rx_err_msg(9)
• es58x_cmd_ret_desc(9) — es58x_rx_cmd_ret_u8(9) — es58x_rx_cmd_ret_u32(9)
• es58x_increment_rx_errors(9)
• es58x_handle_urb_cmd(9) — es58x_check_rx_urb(9) — es58x_copy_to_cmd_buf(9)
• es58x_split_urb_try_recovery(9) — es58x_handle_incomplete_cmd(9) — es58x_split_urb(9)
• es58x_read_bulk_callback(9) — es58x_write_bulk_callback(9)
• es58x_get_tx_urb(9) — es58x_submit_urb(9) — es58x_send_msg(9)
• es58x_alloc_rx_urbs(9) — es58x_free_urbs(9)
• es58x_open(9) — es58x_stop(9)
• es58x_xmit_commit(9) — es58x_xmit_more(9) — es58x_start_xmit(9)
• es58x_set_mode(9)
• es58x_init_priv(9) — es58x_init_netdev(9) — es58x_free_netdevs(9) — es58x_init_es58x_dev(9)
• es58x_probe(9) — es58x_disconnect(9)

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💡 reminder bestie: this is a Kernel API Manual page, so everything above is fr fr official — don't go inventing behavior on me 🙈

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and that's the page!! 🍓 this lil drop ships from ./drivers/net/can/usb/etas_es58x, dated October 2026, and it's literally called es58x_alloc_urb(9). go read some more kernel docs, bestie, you're doing amazing 🧚‍♀️💜